Transmitting apparatus, receiving apparatus and controlling method thereof

ABSTRACT

Provided are a transmitting apparatus, a receiving apparatus and controlling methods thereof. The transmitting apparatus includes: at least one processor configured to implement a packet generator which generates a packet including a header and a payload based on a plurality of input packets; and a signal processor which signal-processes the generated packet, and a transmitter configured to transmit the signal-processed packet. A base field included in the header includes a first field set to a first value representing that the base field is a first length or a second value representing that the base field is a second length.

CROSS-REFERENCE TO THE RELATED APPLICATIONS

This application claims priority from U.S. Provisional PatentApplication Nos. 62/077,970 and 62/151,654, filed on Nov. 11, 2014 andApr. 23, 2015, in the U.S. Patent Trademark Office, and Korean PatentApplication No. 10-2015-0158268, filed on Nov. 11, 2015, in the KoreanIntellectual Property Office, the disclosures of which are incorporatedherein by reference in its entirety.

BACKGROUND

1. Field

Apparatuses and methods consistent with the exemplary embodiments relateto a transmitting apparatus, a receiving apparatus, and a signalingmethod thereof, which transmit data by mapping the data to at least onesignal processing path.

2. Description of the Related Art

In the information-oriented society of the 21^(st) century, broadcastingcommunication services are entering an era of digitization,multi-channel, broadband, and high quality. In particular, ashigh-quality digital television (TV), portable multimedia players (PMP),and portable broadcasting apparatuses have been increasingly used inrecent years, even in digital broadcasting services, a demand forsupporting various receiving methods has been increased.

In an actual state in which the standard group has established variousstandards according to demands to provide various services to satisfyuser's needs, it is required to find methods for providing betterservices having improved performance.

SUMMARY

Exemplary embodiments may overcome the above disadvantages and otherdisadvantages not described above. However, the exemplary embodimentsare not required to overcome the disadvantages described above, and maynot overcome any of the problems described above.

The exemplary embodiments provide a transmitting apparatus, a receivingapparatus, and a control method, capable of generating a frame having aformat suitable for transmitting various types of data.

According to an aspect of an exemplary embodiment, there is provided atransmitting apparatus which may include: at least one processorconfigured to implement a packet generator generating a packet includinga header and a payload based on a plurality of input packets, and asignal processor signal-processing the generated packet; and atransmitter configured to transmit the signal-processed packet. A basefield included in the header includes a first field set to a first valuerepresenting that the base field is a first length or a second valuerepresenting that the base field is a second length. When the firstfield is set to the second value, the base field comprises a secondfield representing least significant bits (LSB) of the pointer valueindicating a first start point among respective start points of theinput packets included in the payload and a third field representingmost significant bits (MSB) of the pointer value.

Here, the base field comprises a fourth field representing an extensionmode of the header, and the fourth field comprises at least one ofinformation about whether an optional field is present, a length of theoptional field, and a structure of an extension field.

Further, the fourth field is set to one of a third value representingthat the optional field and the extension field are not present, afourth value representing that the optional field is present and alength of the optional field is 1 byte, a fifth value representing thatthe optional field is present and the length of the optional field is 2bytes, and a sixth value representing the optional field is present, thelength of the optional field is 2 bytes, and the extension field has astructure comprising a plurality of extension payloads.

Further, when the fourth field is set to the fourth value or the fifthvalue, the optional field further includes a fifth field representing atype of extension payload included in the extension field and a sixthfield representing a length of the extension field, and when the fifthfield is set to the predetermined value, the extension field iscompletely filled padding.

Further, when the fourth field is set to the fifth value, the optionalfield comprises a field representing a type of an extension payloadincluded in the extension field, a field representing an LSB part of alength of the extension field, and a field representing an MSB part ofthe length of the extension field.

Further, when the fourth field is set to the sixth value, the optionalfield comprises a field representing a number of a plurality ofextension payloads included in the extension field, a field representingan LSB part of a length of the extension field, and a field representingan MSB part of the length of the extension field.

Further, the extension field comprises a plurality of fieldsrepresenting respective types of the plurality of extension payloads anda plurality of fields representing respective lengths of the pluralityof extension payloads.

Further, when the fourth field is set to one of a fourth value and afifth value and a length of an extension payload included in theextension field is smaller than a length of the extension field, theextension field comprises the extension payload and padding.

Further, when the fourth field is set to a sixth value, the extensionfield comprises a plurality of extension payloads and padding.

According to another aspect of an exemplary embodiment, there isprovided a receiving apparatus which may include: a receiver configuredto receive a stream including a packet including a header and a payload;and at least one processor configured to implement an informationextractor extracting the header from the packet and extract informationincluded in the header, and a signal processor signal-processing aplurality of input packets included in the payload based on theextracted information. A base field included in the header includes afirst field set to a first value representing that the base field is afirst length or a second value representing that the base field is asecond length. When the first field is set to the second value, the basefield comprises a second field representing least significant bits (LSB)of the pointer value indicating a first start point among respectivestart points of the input packets included in the payload and a thirdfield representing most significant bits (MSB) of the pointer value.

According to yet another aspect of an exemplary embodiment, there isprovided a controlling method of a transmitting apparatus which mayinclude: generating a packet including a header and a payload based on aplurality of input packets; signal-processing the generated packet; andtransmitting the signal-processed packet. A base field included in theheader includes a first field set to a first value representing that thebase field is a first length or a second value representing that thebase field is a second length. When the first field is set to the secondvalue, the base field comprises a second field representing leastsignificant bits (LSB) of the pointer value indicating a first startpoint among respective start points of the input packets included in thepayload and a third field representing most significant bits (MSB) ofthe pointer value.

Further, the base field comprises a fourth field representing anextension mode of the header, and the fourth field comprises at leastone of information about whether an optional field is present, a lengthof the optional field, and a structure of an extension field.

Further, the fourth field is set to one of a third value representingthat the optional field and the extension field are not present, afourth value representing that the optional field is present and alength of the optional field is 1 byte, a fifth value representing thatthe optional field is present and the length of the optional field is 2bytes, and a sixth value representing the optional field is present, thelength of the optional field is 2 bytes, and the extension field has astructure comprising a plurality of extension payloads.

Further, when the fourth field is set to the fourth value or the fifthvalue, the optional field further includes a fifth field representing atype of extension payload included in the extension field and a sixthfield representing a length of the extension field, and when the fifthfield is set to the predetermined value, the extension field iscompletely filled by padding.

Further, when the fourth field is set to the fifth value, the optionalfield comprises a field representing a type of an extension payloadincluded in the extension field, a field representing an LSB part of alength of the extension field, and a field representing an MSB part ofthe length of the extension field.

Further, when the fourth field is set to the sixth value, the optionalfield comprises a field representing a number of a plurality ofextension payloads included in the extension field, a field representingan LSB part of a length of the extension field, and a field representingan MSB part of the length of the extension field.

Further, the extension field comprises a plurality of fieldsrepresenting respective types of the plurality of extension payloads anda plurality of fields representing respective lengths of the pluralityof extension payloads.

Further, when the fourth field is set to one of a fourth value and afifth value and a length of an extension payload included in theextension field is smaller than a length of the extension field, theextension field comprises the extension payload and padding.

Further, when the fourth field is set to a sixth value, the extensionfield comprises a plurality of extension payloads and padding.

According to still another aspect an exemplary embodiment, there isprovided a controlling method of a receiving apparatus which mayinclude: receiving a stream including a packet including a header and apayload; extracting the header from the packet and extractinginformation included in the header; and signal-processing a plurality ofinput packets included in the payload based on the extractedinformation. A base field included in the header includes a first fieldset to a first value representing that the base field is a first lengthor a second value representing that the base field is a second length.The header may include a first field which is set to a first valuerepresenting that a pointer value indicating a first start point amongrespective start points of the input packets included in the payload isless than a predetermined value or a second value representing that thepointer value is equal to or greater than the predetermined value. Whenthe first field is set to the second value, the base field comprises asecond field representing least significant bits (LSB) of the pointervalue indicating a first start point among respective start points ofthe input packets included in the payload and a third field representingmost significant bits (MSB) of the pointer value.

According to the exemplary embodiments, since an input stream can beefficiently mapped to a physical layer, data processing efficiency canbe improved.

Additional and/or other aspects and advantages of the exemplaryembodiments will be set forth in part in the description which followsand, in part, will be obvious from the description, or may be learned bypractice of the exemplary embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects will be more apparent by describingcertain exemplary embodiments with reference to the accompanyingdrawings, in which:

FIG. 1 is a diagram for describing a hierarchical structure of atransmitting system, according to an exemplary embodiment;

FIG. 2 is a diagram illustrating a schematic configuration of abroadcast link layer 1400, according to an exemplary embodiment;

FIG. 3A is a diagram for describing a schematic configuration of atransmitting system, according to an exemplary embodiment;

FIGS. 3B and 3C are diagrams for describing a multiplexing method,according to exemplary embodiments;

FIG. 4 is a block diagram illustrating a detailed configuration of aninput formatting block illustrated in FIG. 3A, according to an exemplaryembodiment;

FIG. 5A is a block diagram illustrating a configuration of a basebandformatting block, according to an exemplary embodiment, and FIG. 5B is adiagrams for describing a detailed configuration of a baseband packet,according to an exemplary embodiment;

FIG. 6 is a block diagram illustrating a configuration of a transmittingapparatus, according to an exemplary embodiment;

FIG. 7A is a block diagram illustrating a detailed configuration of apacket generator, according to an exemplary embodiment, and FIG. 7B is adiagram illustrating an ALP packet, a baseband packet, and a scrambledbaseband packet according to an exemplary embodiment;

FIG. 8 is a diagram illustrating a packet structure, according to anexemplary embodiment;

FIG. 9 is a diagram illustrating a header structure, according to anexemplary embodiment;

FIG. 10 is a diagram illustrating a detailed configuration of anoptional field, according to an exemplary embodiment;

FIGS. 11 to 16D are diagrams illustrating structures of a packet,according to exemplary embodiments;

FIG. 17 is a diagram illustrating a structure of a packet, according toanother exemplary embodiment;

FIG. 18 is a diagram illustrating a detailed configuration of a headerillustrated in FIG. 17, according to an exemplary embodiment;

FIG. 19 is a diagram illustrating a detailed configuration of anoptional field, according to another exemplary embodiment;

FIGS. 20 to 24 are diagrams illustrating structures of a packet,according to exemplary embodiments;

FIG. 25 is a diagram illustrating a structure of an extension field,according to an exemplary embodiment;

FIG. 26A is a block diagram illustrating a configuration of a receivingapparatus, according to an exemplary embodiment;

FIG. 26B is a block diagram illustrating a signal processor, accordingto an exemplary embodiment in detail;

FIG. 27 is a block diagram illustrating a configuration of a receiver,according to an exemplary embodiment;

FIG. 28 is a block diagram illustrating a demodulator, according to anexemplary embodiment in more detail;

FIG. 29 is a flowchart schematically illustrating an operation of areceiver, according to an exemplary embodiment;

FIG. 30 is a flowchart for describing a control method of a transmittingapparatus, according to an exemplary embodiment; and

FIG. 31 is a flowchart for describing a control method in a receivingapparatus, according to an exemplary embodiment.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Hereinafter, various exemplary embodiments of the inventive concept willbe described in detail with reference to the accompanying drawings.Further, in the following description, a detailed explanation of knownrelated functions or configurations may be omitted to avoidunnecessarily obscuring the subject matter. In addition, terms to bedescribed below may vary according to a user's and an operator'sintentions, the convention, or the like as terms defined by consideringfunctions. Therefore, the definition should be made according to thecontents throughout this specification.

An apparatus and a method proposed in the exemplary embodiments can be,of course, applied to various communication systems including mobilebroadcasting services including a digital multimedia broadcasting (DMB)service, digital video broadcasting handheld (DVP-H), an advancedtelevision systems committee mobile/handheld (ATSC-M/H) service, anInternet protocol television (IPTV), and the like, communication systemsincluding a moving picture experts group (MPEG) media transport (MMT)system, an evolved packet system (EPS), a long-terms evolution (LTE)mobile communication system, a long-term evolution-advanced (LTE-A)mobile communication system, a high speed downlink packet access (HDSPA)mobile communication system, a high speed uplink packet access (HSUPA)mobile communication system, a 3^(rd) generation project partnership 2(3GPP2) high rate packet data (HRPD) mobile communication system, a3GPP2 wideband code division multiple access (WCDMA) mobilecommunication system, a 3GPP2 code division multiple access (CDMA)mobile communication system, an Institute of Electrical and ElectronicsEngineers (IEEE) 802.16m communication system, a mobile Internetprotocol (Mobile IP) system, and the like.

FIG. 1 is a diagram illustrating a hierarchical structure of atransmitting system according to an exemplary embodiment.

Referring to FIG. 1, a service includes media data 1000 and signaling1050 for transferring information required to acquire and consume themedia data at a receiver. The media data may be encapsulated in a formatsuitable for transmission prior to the transmission. An encapsulationmethod may follow a Media Processor (MPU) defined in ISO/IEC 23008-1MPEG Media Transport (MMT) or a DASH segment format defined in ISO/IEC23009-1 Dynamic Adaptive Streaming over HTTP (DASH). The media data 1000and the signaling 1050 are packetized according to an application layerprotocol.

FIG. 1 illustrates a case in which an MMT protocol (MMTP) 1110 definedin the MMT and a Real-Time Object Delivery over Unidirectional Transport(ROUTE) protocol 1120 are used as the application layer protocol. Inthis case, a method for notifying information about an applicationprotocol, in which a service is transmitted, by an independent methoddifferent from the application layer protocol is required for thereceiver to know by which application layer protocol the service istransmitted.

A service list table (SLT) 1150 illustrated in FIG. 1 represents orindicates a signaling method and packetizes information about theservice in a table for satisfying the aforementioned object. Detailedcontents of the SLT will be described below. The packetized media dataand the signaling including the SLT are transferred to a broadcastinglink layer 1400 through a user datagram protocol (UDP) 1200 and anInternet protocol (IP) 1300. An example of the broadcasting link layer1400 includes an ATSC 3.0 link-layer protocol (ALP) defined in the ATSC3.0 standard (hereafter, referred to as ‘ATSC 3.0’). The ALP protocolgenerates an ALP packet by using an IP packet as an input, and transfersthe ALP packet to a broadcasting physical layer 1500.

However, according to FIG. 2 to be described below, it is noted that thebroadcasting link layer 1400 does not use only the IP packet 1300including the media data and/or the signaling as the input, and instead,may use an MPEG2-TS packet or general formatted packetized data as theinput. In this case, signaling information required to control thebroadcasting link layer is also transferred to the broadcasting physicallayer 1500 in the form of the ALP packet.

The broadcasting physical layer 1500 generates a physical layer frame bysignal-processing the ALP packet as the input, converts the physicallayer frame into a radio signal, and transmits the radio signal. In thiscase, the broadcasting physical layer 1500 has at least one signalprocessing path. An example of the signal processing path may include aphysical layer pipe (PLP) of ATSC 3.0 or the Digital VideoBroadcasting-Second Generation Terrestrial (DVB-T2) standard, and one ormore services or some of the services may be mapped to the PLP.

FIG. 2 is a diagram illustrating a schematic configuration of thebroadcasting link layer 1400, according to an exemplary embodiment.

Referring to FIG. 2, the input of the broadcasting link layer 1400includes the IP packet 1300, and may further include link layersignaling 1310, an MPEG2-TS packet 1320, and other packetized data 1330.

Input data may be subjected to additional signal processing based on thetype of the input data before ALP packetization 1450. As an example ofthe additional signal processing, the IP packet 1300 may be subjected toan IP header compression process 1410 and the MPEG2-TS packet may besubjected to an overhead reduction process 1420. During the ALPpacketization, input packets may be subjected to dividing and mergingprocesses.

FIG. 3A is a diagram illustrating a schematic configuration of atransmitting system or a transmitting apparatus, according to anexemplary embodiment. According to FIG. 3A, a transmitting system 10000according to the exemplary embodiment may include input formattingblocks 11000 and 11000-1, bit interleaved and coded modulation (BICM)blocks 12000 and 12000-1, framing/interleaving blocks 13000 and 13000-1,and waveform generation blocks 14000 and 14000-1.

The input formatting blocks 11000 and 11000-1 generate a baseband packetfrom an input stream of data to be serviced. Herein, the input streammay be a transport stream (TS), Internet packets (IP) (e.g., IPv4 andIPv6), an MPEG media transport (MMT), a generic stream (GS), genericstream encapsulation (GSE), and the like. For example, an ATSC 3.0link-layer protocol (ALP) packet may be generated based on the inputstream, and the baseband packet may be generated based on the generatedALP packet.

The bit interleaved and coded modulation (BICM) blocks 12000 and 12000-1determine an forward error correction (FEC) coding rate and aconstellation order according to an area (fixed PHY frame or mobile PHYframe) to which the data to be serviced will be transmitted, and performencoding and time interleaving. Meanwhile, signaling information aboutthe data to be serviced may be encoded through a separate BICM encoderaccording to user implementation or encoded by sharing a BICM encoderwith the data to be serviced.

The framing/interleaving blocks 13000 and 13000-1 combine thetime-interleaved data with a signaling signal including the signalinginformation to generate a transmission frame.

The waveform generation blocks 14000 and 14000-1 generate an orthogonalfrequency-division multiplexing (OFDM) signal in a time domain for thegenerated transmission frame, modulate the generated OFDM signal into anRF signal, and transmit the RF signal to a receiver.

The transmitting system 10000 according to the exemplary embodimentillustrated in FIG. 3A includes normative blocks marked with a solidline and informative blocks marked with dotted lines. Herein, the blocksmarked with the solid line are normal blocks, and the blocks marked withthe dotted lines are blocks which may be used when informativemultiple-input multiple-output (MIMO) is implemented.

FIGS. 3B and 3C are diagrams illustrating a multiplexing method,according to exemplary embodiments.

FIG. 3B illustrates a block diagram for implementing time divisionmultiplexing (TDM), according to an exemplary embodiment.

A TDM system architecture includes four main blocks (alternatively,parts) of the input formatting block 11000, the BICM block 12000, theframing/interleaving block 13000, and the waveform generation block14000.

Data is input and formatted in the input formatting block 11000 andforward error correction is applied the data in the BICM block 12000.Next, the data is mapped to a constellation. Subsequently, the data istime and frequency-interleaved in the framing/interleaving block 13000and a frame is generated. Thereafter, an output waveform is generated inthe waveform generation block 14000.

FIG. 3C illustrates a block diagram for implementing layered divisionmultiplexing (LDM), according to an exemplary embodiment.

An LDM system architecture includes several other blocks as comparedwith the TDM system architecture. In detail, two separated inputformatting blocks 11000 and 11000-1 and the BCIM blocks 12000 and12000-1 for one of respective layers of the LDM are included in the LDMsystem architecture. The blocks are combined in an LDM injection blockbefore the framing/interleaving block 13000. And, the waveformgeneration block 14000 is similar to the TDM.

FIG. 4 is a block diagram illustrating a detailed configuration of theinput formatting block illustrated in FIG. 3A, according to an exemplaryembodiment.

As illustrated in FIG. 4, the input formatting block 11000 includesthree blocks that control packets distributed to PLPs. In detail, theinput formatting block 11000 includes an encapsulation and compressionblock 11100, a baseband formatting block (alternatively, basebandframing block) 11300, and a scheduler block 11200.

An input stream input to the encapsulation and compression block 11100may be various types. For example, the input stream may be a transportstream (TS), an Internet packets (IP) (e.g., IPv4 and IPv6), an MPEGmedia transport (MMT), a generic stream (GS), a generic streamencapsulation (GSE), and the like.

Packets output from the encapsulation and compression block 11100 becomeALP packets (generic packets) (also referred to as L2 packets). Herein,a format of an ALP packet may be one of the Type Length Value (TLV), theGSE, and the ALP.

The length of each ALP packet is variable. The length of the ALP packetmay be easily extracted from the ALP packet itself without additionalinformation. The maximum length of the ALP packet is 64 kB. The maximumlength of a header of the ALP packet is 4 bytes. The ALP packet has alength of integer bytes.

The scheduler block 11200 receives an input stream including theencapsulated ALP packets to form physical layer pipes (PLPs) in abaseband packet form. In the TDM system, only one PLP called a singlePLP (S-PLP) or multiple PLPs (M-PLP) may be used. One service may notuse four or more PLPs. In the LDM system constituted by two layers, onein each layer, that is, two PLPs are used.

The scheduler block 11200 receives the encapsulated ALP packets todesignate how the encapsulated ALP packets are allocated to physicallayer resources. In detail, the scheduler block 11200 designates how thebaseband formatting block 1130 outputs a baseband packet.

A function of the scheduler block 11200 is defined by a data size and atime. A physical layer may transmit some of data in the distributedtime. The scheduler block generates a solution which is suitable interms of a configuration of a physical layer parameter by using inputsand information such as constraints and configuration from anencapsulated data packet, the quality of service metadata for theencapsulated data packet, a system buffer model, and system management.The solution is targets of a configuration and a control parameter whichare usable and an aggregate spectrum.

Meanwhile, an operation of the scheduler block 11200 is constrained to aset of dynamic, quasi-static, and static components. Definition of theconstraint may vary according to user implementation.

Further, a maximum of four PLPs may be used with respect to eachservice. A plurality of services which include a plurality of types ofinterleaving blocks may be implemented by up to a maximum of 64 PLPswith respect to a bandwidth of 6, 7, or 8 MHz.

The baseband formatting block 11300 includes baseband packetconstruction blocks 3100, 3100-1, . . . 3100-n, baseband packet headerconstruction blocks 3200, 3200-1, . . . , 3200-n, and baseband packetscrambling blocks 3300, 3300-1, . . . , 3300-n, as illustrated in FIG.5A. In an M-PLP operation, the baseband formatting block generates aplurality of PLPs as necessary.

The baseband packet construction blocks 3100, 3100-1, . . . , 3100-nconstruct baseband packets. Each baseband packet 3500 includes a header3500-1 and a payload 3500-2 as illustrated in FIG. 5B. A baseband packetis fixed to a length Kpayload. ALP packets 3610 to 3650 are sequentiallymapped to a baseband packet 3500. When the ALP packets 3610 to 3650 donot completely fit in the baseband packet 3500, these packets aredistributed between a current baseband packet and a next basebandpacket. The ALP packets are distributed in a unit of a byte.

The baseband packet header construction blocks 3200, 3200-1, . . . ,3200-n construct a header 3500-1. The header 3500-1 includes threeparts, that is, a base field (also referred to as, a base header) 3710,an optional field (also referred to as, an option header) 3720, and anextension field (also referred to as, an extension header) 3730, asillustrated in FIG. 5B. Herein, the base field 3710 is shown in everybaseband packet and the optional field 3720 and the extension field 3730may not be shown in every baseband packet.

A main function of the base field 3710 provides a pointer of an offsetvalue as bytes to indicate a start of a next ALP packet in a basebandpacket. When an ALP packet starts a baseband packet, the value of thepointer becomes 0. When there is no ALP packet that starts in thebaseband packet, the value of the pointer may be 8191 and a base headerof 2 bytes may be used.

The extension field 3730 may be used afterwards and for example, usedfor a baseband packet counter, baseband packet time stamping, additionalsignaling, and the like.

The baseband packet scrambling blocks 3300, 3300-1, . . . , 3000-nscramble the baseband packet.

FIG. 6 is a block diagram illustrating a configuration of a transmittingapparatus according to an exemplary embodiment.

Referring to FIG. 6, a transmitting apparatus 100 includes a packetgenerator 110, a signal processor 120, and a transmitter 130.

The packet generator 110 may generate a packet including a header and apayload, for example, a baseband packet (alternatively, an L1 packet)based on an input packet. Here, the packet includes the header and thepayload including the input packet, and is defined as a k payload havinga fixed length. The length of the packet may be set according toselected code rate and code length. Here, the input packet may be, forexample, an ATSC link layer protocol (ALP) packet. The ALP packetincludes one of an internal protocol (IP) packet, a transport stream(TS) packet, and a signaling packet or may include a combinationthereof. In detail, the input IP packet, TS packet, and various types ofdata are encapsulated to be generated as the ALP packet for transmissionto each PLP and the ALP packet corresponds to an L2 packet in an ISO 7layer model. Further, the data included in the payload is not limited tothe aforementioned example, and the payload may include various types ofdata. Hereinafter, for convenience of description, the packet generatedby the packet generator 110 is called a baseband packet and the inputpacket is called an ALP packet.

A process of generating the baseband packet will be described withreference to FIGS. 7A and 7B.

FIG. 7A is a block diagram illustrating a detailed configuration of apacket generator according to an exemplary embodiment.

Referring to FIG. 7A, the packet generator 110 may include a basebandpacket header generator 110-1 and a baseband packet constructor 110-2.In addition, the packet generator 110 may transmit a generated basebandpacket to a baseband packet scrambler 115.

In addition, an ALP packet constructor 110′ may generate an ALP packetfor transmitting to each PLP in association with an input mode from aninput IP packet, a TS packet, and various types of data. Herein, the ALPpacket corresponds to an L2 packet in an ISO 7 layer model. That is, theALP packet constructor 110′ may generate an ALP packet by encapsulatingthe packets (the IP packet, the TS packet, and the like) input frominput upper layers of Layer 2 or higher.

In detail, the ALP packet constructor 110′ may generate an ALP packet(i.e., an L2 packet) including a header and ALP payload data based onthe input stream. Herein, the header means the header of the ALP packet,and may include information about the ALP payload data included in theALP packet and information about at least one packet included in the ALPpacket.

The baseband packet header generator 110-1 may generate a headerinserted into the baseband packet. Herein, the header inserted into thebaseband packet is referred to as a baseband packet header and thebaseband packet header includes information about the baseband packet.

In particular, the baseband packet header generator 110-1 may generatethe baseband packet header including information about the number of TSpackets in the ALP packet, the number of removed null packets, and thelike when an input stream is a TS. Besides, the baseband packet headergenerated by the baseband packet header generator 110-1 may includevarious information which will be described below.

Further, the baseband packet constructor 110-2 encapsulates the basebandpacket header generated from the baseband packet header generator 110-1in the ALP packet output from the ALP packet constructor 110′ togenerate the baseband packet.

Further, the packet generator 110 arranges a plurality of ALP packetsincluding the IP packet and the header to generate the arranged ALPpackets as a baseband packet having a size corresponding to an FEC code.The baseband packet according to the exemplary embodiment may be a TSpacket, but the same process may be applied to various types of datadescribed above as well as the TS packet.

In addition, the baseband packet scrambler 115 mixes data stored in thebaseband packet in a random order before the FEC code is added to eachbaseband packet to generate the scrambled baseband packet. The scrambledbaseband packet is transmitted through a PLP to be signal-processed. Inthis case, one PLP may be constituted by baseband packets having a fixedsize. That is, the input stream may be encapsulated to the basebandpacket for one PLP.

Meanwhile, the PLP means a signal path which is independently processed.That is, respective services (for example, video, extension video,audio, a data stream, and the like) may be transmitted and receivedthrough multiple RF channels and the PLP is a path through which theservices are transmitted or a stream transmitted through the path.Further, the PLP may be positioned at slots distributed on multiple RFchannels at a time interval or distributed on one RF channel at a timeinterval. That is, one PLP may be transmitted while being distributed onone RF channel or multiple RF channels at a time interval.

A PLP structure is constituted by Input mode A providing one PLP andInput mode B providing multiple PLPs. When the PLP structure supportsthe Input mode B, the PLP structure may provide a strong specificservice and a time interleaving length is increased by distributing andtransmitting one stream to acquire a time diversity gain. Further, whenonly a specific stream is received, a power supply of the receiver isturned off for a residual time to be used with low power, and as aresult, the receiver is suitable for providing portable and mobilebroadcasting services.

Herein, the time diversity is technology that when a transmitting sidetransmits the same signal at a predetermined time interval several timesin order to reduce deterioration of a transmission quality in a mobilecommunication transmission path, a receiving side synthesizes thereceived signals again to acquire excellent transmission quality.

Further, information which may be commonly transmitted to a plurality ofPLPs is transmitted while being included in one PLP to increasetransmission efficiency. In this case, PLP0 performs such a role and thePLP is referred to as a common PLP, and residual PLPs other than thePLP0 may be used for data transmission and the PLP is referred to as adata PLP. When such a PLP is used, a home HDTV program may be receivedand an SDTV program may be provided even while carrying and moving.Further, various broadcasting services may be provided to a viewerthrough a broadcasting station or a broadcasting content provider anddifferentiated services in which a broadcast may be received may beprovided even in a fringe area where viewing is difficult.

Meanwhile, FIG. 7B is a diagram illustrating an ALP packet, a basebandpacket, and a scrambled baseband packet according to an exemplaryembodiment.

Referring to FIG. 7B, when the ALP packet constructor 110′ stores the TSpacket in the ALP payload and inserts the header to generate a pluralityof ALP packets 111′ and 112′, the packet generator 130 groups theplurality of generated ALP packets 111′ and 112′ and inserts thebaseband packet header to generate a plurality of baseband packets 121and 122. Herein, the respective baseband packets 121 and 122 may includea plurality of ALP packets and further, may include some of the ALPpackets.

The baseband packet scrambler 115 randomly scrambles the basebandpackets 121 and 122 to generate a plurality of scrambled basebandpackets 125-1 and 125-2. In addition, the scrambled baseband packets125-1 and 125-2 are transmitted to the PLP as described above andsubjected to signal processing for adding the FEC code.

Referring back to FIG. 6, the signal processor 120 may signal-processthe generated packet. Here, the generated packet means the basebandpacket as described above.

In detail, the signal processor 120 signal-processes the baseband packetto generate a transmission frame.

Further, the signal processor 120 may insert signaling information intoa signaling area of the frame. Herein, the signaling information may bea layer 1 (L1) signaling signal transmitting an L1 signal for framesynchronization, and a preamble into which the L1 signaling informationis inserted may include an L1 pre signaling area and an L1 postsignaling area. Further, the L1 post signaling area includes aconfigurable field and a dynamic field.

Meanwhile, the L1 pre signaling area may include information foranalyzing the L1 post signaling and information about the entire system,and the L1 pre signaling area may be implemented to have the same lengthat all times. Further, the L1 post signaling area may includeinformation about the respective PLP and information about the system,and in one superframe, the L1 signaling areas included in respectiveframes have the same length, but contents included in the L1 signalingareas may vary.

Meanwhile, although not illustrated, the signal processor 120 mayperform functions corresponding to bit interleaved and coded modulation(BICM) blocks 12000 and 12000-1 and framing/interleaving blocks 13000and 13000-1 illustrated in FIGS. 3A to 3C.

The transmitter 130 may transmit the signal-processed frame to areceiving apparatus (not illustrated).

In detail, the transmitter 130 may perform functions corresponding towaveform generation blocks 14000 and 14000-1 illustrated in FIGS. 3A to3C. That is, the transmitter 130 performs modulation for modulating thegenerated frame to the RF signal, and transmits the RF signal to areceiving apparatus (not illustrated).

Meanwhile, FIG. 8 is a diagram illustrating a packet structure accordingto an exemplary embodiment. Here, it is defined in advance that thepacket generated from the packet generator 110 used in thisspecification means a baseband packet.

Referring to FIG. 8, the baseband packet is constituted by a header 3100and a payload 3200. The header 3100 may be again divided into a basefield 3110, an optional field 3120, and an extension field 3130according to a role thereof. Here, the base field will be defined as thesame meaning as the base header. The baseband packet header 3100 maynecessarily include the base field 3110, and whether the optional field3120 is present may vary according to a control field value of the basefield 3110. Further, whether the extension field 3130 is present may beselected by using a control field of the optional field 3120.

Meanwhile, the base field, the optional field, and the extension fieldused in this specification may correspond to a base header, an optionalheader, and an extension header, respectively.

Hereinafter, a structure of the header will be described with referenceto the accompanying drawings. Here, the header may mean a header of thebaseband packet.

FIG. 9 is a diagram illustrating a structure of a header according to anexemplary embodiment.

Referring to FIG. 9, a baseband packet 2300 may include a base header2310, an optional field 2320, an extension field 2330, and a payload2340.

Meanwhile, in this specification, terms such as the base header, theoptional field, and the extension field are used and described, but ofcourse, the terms may be expressed by general words such as a firstheader, a second field, and a third field.

In detail, the baseband packet may be largely divided into a header anda payload, and here, the header may be constituted by three parts asillustrated in FIG. 9. The first part is the base header 2310 and existsin all packets. In addition, the second part is the optional field 2320and the third part is the extension field 2330. The optional field 2320and the extension field 2330 are not always present in all packets, andthe base header 2310 includes information representing (or indicating)whether the optional field 2320 and the extension field 2330 arepresent.

Further, the header may include the base header 2310 includinginformation representing a start point of a data packet in the payload2340 and information about whether an additional field is present. Thatis, the base header 2310 may include information representing the startpoint of the data packet in the payload 2340. In detail, the base header2310 may perform a function of providing a pointer including an offsetvalue of a byte unit up to a start point of a next generic packet (alsoreferred to as “data packet” or “ALP packet”) which is present in thepacket 2300. Here, the start point of the data packet means a distancebetween the start point of the payload 2340 and the start point of thedata packet, and the distance may be expressed by the aforementionedoffset value of the byte unit.

As illustrated in FIG. 7B, a first ALP packet 111′ is not segmented andmay be included in the first packet 121, but may be segmented togetherwith a second ALP packet 112′ to be included in the first packet 121 andthe second packet 122.

In this case, the base header included in the header of the first packet121 may include information representing a start point of the first ALPpacket 111′, and in detail, may include information including a value ofa distance between the payload start point of the first packet 121 andthe start point of the first ALP packet 111′.

Further, the base header included in the header of the second packet 122may include information representing a start point of the ALP packetincluded next to the second packet 112′.

For example, when the generic packet is disposed from the start point inthe packet, a value of the pointer may be set to 0. In addition, thepointer may be extended to 2 bytes, and thus, the value represented bythe pointer may be increased up to 8191. That is, the base header 2310may express the distance to the start point, where the generic packetstarts in the packet, by the value of 8191.

In detail, the information representing the start point of the datapacket (i.e., the ALP packet) may include information about whether amost significant bit (MSB) part of the pointer is present according tothe distance between the start point of the payload and the start pointof the data packet, and may include one of a first value representingthat the MSB part is not present and a second value representing thatthe MSB part is present. That is, when the information representing thestart point of the data packet is set to 0, it represents that the MSBpart is not present, and when the information representing the startpoint of the data packet is set to 1, it represents that the MSB part ispresent.

Referring to FIG. 9, the base header 2310 has a MODE field 2311 thereinwhich includes the information about the start point of the data packet,and the MODE field 2311 represents whether an MSB part of the pointer ispresent. Here, the MODE field 2311 may has a size of 1 bit.

When the MODE field 2311 is set to 0, the MODE field 2311 representsthat a distance from a start point of the payload 2340 to a start pointof a new generic packet (i.e. data packet) in the payload 2340 is ashort pointer length. Here, the short pointer length means a lengthwhich is not beyond 127 bytes. Accordingly, a pointer field includingthe information about the distance from the start point of the payload2340 to the start point of the new generic packet in the payload 2340includes only a pointer (LSB) field 2312 corresponding to the shortpointer length and the pointer (MSB) field 2313 is not included. Here,the length of the pointer (LSB) field 2312 is 7 bits.

Further, when the MODE field 2311 is set to 0, the pointer fieldincludes only the pointer (LSB) field 2312, and thus, the length of thebase header 2310 becomes 1 byte.

Meanwhile, when the MODE field 2311 is set to 1, the MODE field 2311represents that a distance from a start point of the payload 2340 to astart point of a new generic packet in the payload 2340 is a longpointer length. Here, the long pointer length may be equal to or largerthan 128 bytes. Accordingly, a pointer field including the informationabout the distance from the start point of the payload 2340 to the startpoint of the new generic packet in the payload 2340 may include apointer (MSB) field 2313 as well as the pointer (LSB) field 2312 inorder to represent the long pointer length. The length of the pointer(MSB) field 2313 is 6 bits.

Further, when the MODE field 2311 is set to 1, the base header 2310 mayinclude an OHI field 2314 representing information about whether anadditional field is present in the header. The length of the OHI field2314 is 2 bits.

Accordingly, when the MODE field 2311 is set to 1, the base header 2310includes the MODE field 2311, the pointer (LSB) field 2312, the pointer(MSB) field 2313, and the OHI field 2314, and thus, the length of thebase header 2310 becomes 2 bytes.

As a result, the pointer (MSB) field 2313 and the OHI field 2314 may beincluded in the base header 2310 only when the MODE field 2311 is set to1.

Meanwhile, information about whether the additional field is present inthe header may include information about whether at least one of theoptional field 2320 and the extension field 2330 is present and a lengthof the optional field 2320 and the extension field 2330.

Further, the information about whether the additional field is presentmay include one of a first value representing that the optional field2320 and the extension field 2330 are not present, a second valuerepresenting the optional field 2320 is present, the extension field2330 is not present, and the length of the optional field 2320 is 1byte, a third value representing that the optional field 2320 ispresent, the extension field 2330 is not present, and the length of theoptional field 2320 is 2 bytes, and a fourth value representing that theoptional field 2320 and the extension field 2330 are present and thelength of the optional field 2320 and the extension field 2330 exceeds 2bytes.

In addition, the optional field 2320 may include informationrepresenting a length of the extension field 2330 when the informationabout whether the additional field is present is set to the fourth valueand may include at least one of the LSB part and the MSB part accordingto the length of the extension field.

The information about whether the additional field is present may bestored in the optional header indicator (OHI) field 2314. In detail, thelength of the OHI field 2314 is 2 bytes, and the length of the optionalfield 2320 may be equal to or smaller than 2 bytes. Informationrepresenting values stored in the OHI field 2314 may be summarized infollowing Table 1.

TABLE 1 OHI field Content 00 Optional field and extension field are notpresent 01 Optional field is present, extension field is not present,and length of the optional field is 1 byte. 10 Optional field ispresent, extension field is not present, and length of the optionalfield is 2 bytes. 11 Optional field and extension field are present, andlength of the optional field and extension field exceeds 2 bytes. Lengthof optional field is 1 byte or 2 bytes, actual length of the extensionfield is indicated in EXT_LEN field of optional field.

In detail, how the optional field 2320 and the extension field 2330 areincluded in the header according to a value set in the OHI field 2314will be described with reference to FIG. 10.

FIG. 10 is a diagram illustrating a detailed configuration of theoptional field according to an exemplary embodiment.

Referring to FIG. 10, when the OHI field 2314 is set to 00, the headerdoes not include the optional field 2320 and the extension field 2330.

In addition, when the OHI field 2314 is set to 01, the header includesthe optional field 2320 having the length of 1 byte. Here, the optionalfield 2320 may include information representing whether the optionalfield 2320 includes padding. In detail, the optional field 2320 mayinclude an EXT_TYPE field 2321 representing whether the optional field2320 2330 includes padding. Here, the length of the EXT_TYPE field 2321is 3 bits. In addition, a remaining region 2322 of 5 bits except for theEXT_TYPE field 2321 among 1 byte of the optional field 2320 may includepredetermined information or padding. The remaining region 2322 mayinclude the predetermined information or the padding according to theinformation included in the EXT_TYPE field 2321. Here, the padding meansmeaningless data, and the meaningless data may be randomly determined byvarious methods according to a system design. Further, the padding isnot required to be filled only with 0, may be filled only with 1, andmay be filled with a meaningless combination of 0 and 1. However, a casewhere the padding is filled only with 0 will be described as an example.

Further, when the OHI field 2314 is set to 10, the header includes theoptional field 2320 having a length of 2 bytes. Similarly, the optionalfield 2320 may include information representing whether the optionalfield 2320 includes padding. In detail, the optional field 2320 mayinclude an EXT_TYPE field 2321 representing whether the optional field2320 includes padding, and here, the length of the EXT_TYPE field 2321is 3 bits. In addition, remaining 5-bit region 2322 and 8-bit region2323 except for the EXT_TYPE field 2321 among 2 bytes of the optionalfield 2320 may include predetermined information or padding. Theremaining 5-bit region 2322 and 8-bit region 2323 may include thepredetermined information or the padding according to the informationstored in the EXT_TYPE field 2321. Here, the padding means meaninglessdata, and the meaningless data may be randomly determined by variousmethods according to a system design.

Meanwhile, when the OHI field is set to 11, the header may include theextension field 2330 as well as the optional field 2320. Here, a totallength of the optional field 2320 and the extension field 2330 exceeds 2bytes, and the length of the optional field 2320 may be 1 byte or may be2 bytes. Further, the optional field 2320 may include informationrepresenting whether at least one of the optional field 2320 and theextension field 2330 includes padding. In detail, the optional field2320 may include an EXT_TYPE field 2321 representing whether at leastone of the optional field 2320 and the extension field 2330 includespadding, and here, the length of the EXT_TYPE field 2321 is 3 bits.

However, when the OHI field 2314 is set to 11, the EXT_TYPE field 2321sets a value corresponding to a type of the extension field 2330. Forexample, when the padding is stored in the extension field 2330, theEXT_TYPE field 2321 has a value meaning that the padding is stored inthe extension field 2330 is stored. In addition, when the OHI field 2314is set to 11, the optional field 2320 includes information representingthe length of the extension field 2330, and thus, may include at leastone of the LSB part and the MSB part according to the length of theextension field. Here, the optional field 2320 may include at least oneof an EXT_LEN (LSB) field 2324 and an EXT_LEN (MSB) field 2325representing the length of the extension field 2330. The length of theEXT_LEN (LSB) field 2324 may be 5 bits and the length of the EXT_LEN(MSB) field 2325 may be 8 bits.

When summarizing the aforementioned EXT_TYPE field 2321, the EXT_TYPEfield 2321 is a 3-bit field representing a type of the extension field,the OHI field 2314 is set to 01, and when the EXT_TYPE field 2321 is setto 000, a bit sequence of “00000” may be stored in the optional field2320. Further, the OHI field 2314 is set to 10 and when the EXT_TYPEfield 2321 is set to 000, a bit sequence of “00000000” other than thebit sequence of “00000” may be additionally stored in the optional field2320. Further, when the OHI field 2314 is set to 11, the EXT_TYPE field2321 is filled with a value corresponding to the type of the extensionfield 2330 and at least one of the EXT_LEN (LSB) field 2324 and theEXT_LEN (MSB) field 2325 may be connected and disposed. Here, when theEXT_TYPE field 2321 is set to 000, the padding (that is, the bitsequence of 00000 or the bit sequence of 00000000) is filled in theoptional field 2320, but it is just exemplified, and of course, what thevalue set in the EXT_TYPE field 2321 means may vary according to adesign method.

The EXT_LEN (LSB) field 2324 represents the length of the extensionfield 2330 and includes 5 LSB bits of the EXT_LEN field. The EXT_LEN(LSB) field 2324 always exists when the OHI field 2314 is set to 11.

Further, when the EXT_LEN (MSB) field 2325 includes 8 MSB bits of theEXT_LEN field and the EXT_LEN (MSB) field 2325 is present, the optionalfield 2320 includes an EXT_LEN field of a total of 13 bits in which theEXT_LEN (LSB) field 2324 and the EXT_LEN (MSB) field 2325 are connectedto each other. Accordingly, when the length of the extension field 2330is equal to or smaller than the predetermined length, the optional field2320 may include only the EXT_LEN (LSB) field 2324. When the length ofthe extension field 2330 is greater than the predetermined length, theoptional field 2320 may include both the EXT_LEN (LSB) field 2324 andthe EXT_LEN (MSB) field 2325.

Meanwhile, how the structure of the packet 2300 is entirely changedaccording to the values set in the MODE field 2311 and the OHI field2314 will be described with reference to FIGS. 11 to 16D.

FIGS. 11 to 16D are diagrams illustrating structures of the packetaccording to various exemplary embodiments.

Referring to FIG. 11, when the MODE field 2311 is set to 0, the MODEfield 2311 means the short pointer length, and thus, the base header2310 includes only the pointer (LSB) field 2312. When the MODE field2311 is set to 0, the optional field 2320 and the extension field 2330are not included in the packet 2300, and as a result, the packet 2300includes the base header having the length of 1 byte and the payload2340.

Referring to FIG. 12, when the MODE field 2311 is set to 1, the MODEfield 2311 means the long pointer length, and thus, the base header 2310includes the pointer (LSB) field 2312 and the pointer (MSB) field 2313,and may additionally include the OHI field 2314 including theinformation about whether the optional field 2320 and the extensionfield 2330 are present.

Accordingly, the packet 2300 includes the base header 2340 having thelength of 2 bytes. However, in FIG. 12, when the OHI field 2314 is setto 00, the optional field 2320 and the extension field 2330 are notincluded in the packet 2300, and as a result, the packet 2300 includesthe base header 2310 having a length of 2 bytes and the payload 2340.

Referring to FIG. 13, when the MODE field 2311 is set to 1, the MODEfield 2311 means the long pointer length, and thus, the base header 2310includes the pointer (LSB) field 2312 and the pointer (MSB) field 2313and may additionally include the OHI field 2314 including theinformation about whether the optional field 2320 and the extensionfield 2330 are present.

Accordingly, the packet 2300 includes the base header 2340 having thelength of 2 bytes. However, in FIG. 13, the OHI field 2314 is set to 01and thus, the optional field 2320 having a length of 1 byte is includedin the packet 2300 and the extension field 2330 is not included in thepacket 2300. As a result, the packet 2300 includes the base headerhaving a length of 2 bytes, the optional field 2320 having a length of 1byte, and the payload 2340. Further, the optional field 2320 may includethe EXT_TYPE field 2321 of 3 bits and a padding field 2322 of 5 bits.

Referring to FIG. 14, when the MODE field 2311 is set to 1, the MODEfield 2311 means the long pointer length, and thus, the base header 2310includes the pointer (LSB) field 2312 and the pointer (MSB) field 2313and may additionally include the OHI field 2314 including theinformation about whether the optional field 2320 and the extensionfield 2330 are present.

Accordingly, the packet 2300 includes the base header 2340 having thelength of 2 bytes. However, in FIG. 14, the OHI field 2314 is set to 10and thus, the optional field 2320 having a length of 2 bytes is includedin the packet 2300 and the extension field 2330 is not included in thepacket 2300. As a result, the packet 2300 includes the base header 2310having a length of 2 bytes, the optional field 2320 having a length of 2bytes, and the payload 2340. Further, the optional field 2320 mayinclude the EXT_TYPE field 2321 of 3 bits, a padding field 2322 of 5bits, and a padding field 2323 of 8 bits.

Referring to FIG. 15, when the MODE field 2311 is set to 1, the MODEfield 2311 means the long pointer length, and thus, the base header 2310includes the pointer (LSB) field 2312 and the pointer (MSB) field 2313and may additionally include the OHI field 2314 including theinformation about whether the optional field 2320 and the extensionfield 2330 are present.

Accordingly, the packet 2300 includes the base header 2340 having thelength of 2 bytes. However, in FIG. 15, the OHI field 2314 is set to 11to include the base header 2310 having the length of 2 bytes, theoptional field 2320 having the length of 2 bytes, the extension field2330, and the payload 2340. Further, the optional field 2320 may includethe EXT_TYPE field 2321, the EXT_LEN(LSB) field 2324, and the EXT_LEN(MSB) field 2325.

In FIG. 15, the case where the optional field 2320 includes both theEXT_LEN (LSB) field 2324 and the EXT_LEN (MSB) field 2325 isillustrated. However, the optional field 2320 may include only theEXT_LEN (LSB) field 2324. In this case, the packet 2300 may include thebase header 2310 having the length of 2 bytes, the optional field 2320having the length of 1 byte, the extension field 2330, and the payload2340.

Further, in the aforementioned example, the case where the optionalfield 2320 has at least one of the padding field 2322 of 5 bits and thepadding field 2323 of 8 bits is exemplified, but the optional field 2320may include predetermined data other than the padding and the EXT_TYPEfield 2321 may also include a value representing the predetermined data.

Meanwhile, FIGS. 16A to 16D illustrate that the data filled in theoptional field 2320 and the extension field 2330 may vary according tothe value set in the EXT_TYPE field 2321 when the OHI field 2314 is setto 11.

Referring to FIG. 16A, when the OHI field is set to 11, the optionalfield 2320 includes a TYPE field 2321, an EXT_LEN (LSB) field 2324, andan EXT_LEN (MSB) field 2325, and a representative example where theextension field 2330 is present is illustrated.

Here, when the TYPE field 2321 is set to 001, the optional field 2320may include only the EXT_LEN (LSB) field 2324, and the extension field2330 may include an input stream synchronization (ISSY) field 2331 and apadding 2332. Here, the ISSY field 2331 is exemplified in order todescribe a case where the extension field 2330 includes predetermineddata. The ISSY field 2331 is used to transmit a clock counter valueaccording to a clock modulation ratio and regenerate accurate timing forrestoring an output stream by a receiver of the transmission frame.

Further, referring to FIG. 16B, when the TYPE field 2321 is set to 010,the optional field 2320 may include the EXT_LEN (LSB) field 2324 and theEXT_LEN (MSB) field 2325, and the extension field 2330 may include anISSY field 2333 and a padding 2332.

Of course, the extension field 2330 may include various data other thanthe ISSY field 2333 as the predetermined data. Referring to FIG. 16C,when the TYPE field 2321 is set to 011, the optional field 2320 includesthe EXT_LEN (LSB) field 2324 and the EXT_LEN (MSB) field 2325, and theextension field 2330 may include an in-band signal TYPE A field 2334 anda padding 2332. Referring to FIG. 16D, when the TYPE field 2321 is setto 100, the optional field 2320 includes the EXT_LEN (LSB) field 2324and the EXT_LEN (MSB) field 2325, and the extension field 2330 mayinclude an in-band signal TYPE B field 2335 and a padding 2332.

Meanwhile, the terms used in describing the aforementioned ALP packetand baseband packet may vary according to the system, and for example,the aforementioned ALP packet and baseband packet may be referred to asa baseband packet and a baseband frame, respectively, according to thesystem.

According to another exemplary embodiment, the optional field and theextension field may include fields having different structures and thiswill be described in detail with reference to FIGS. 17 to 25. Further,before describing that the optional field and the extension field mayinclude fields having different structures, description for a fieldincluded in a base field to be described below may correspond to aportion described in FIG. 9, but will be described again by usinggeneral terms.

Referring back to FIG. 6, the transmitting apparatus 100 includes apacket generator 110, a signal processor 120, and a transmitter 130, andthe packet generator 110 may generate a packet including a header and apayload based on an input packet.

Here, the input packet may be, for example, an ALP packet (also referredto as an L2 packet) and the packet generated in the packet generator 110may be a baseband packet (BBP) (also referred to as an L1 packet). Ofcourse, as described above, the terms of the packets may vary accordingto the system and for example, the aforementioned ALP packet and BBPpacket may be referred to as the BBP packet and a baseband frame (BBF),respectively, according to the system.

The packet, that is, the baseband packet may include a header and apayload including an input packet, and the packet is defined as a Kpayload with a fixed length. The length of the packet may be setaccording to selected code rate and code length.

In addition, the input packet, that is, the ALP packet includes one ofan internal protocol (IP) packet, a TS packet, and a signaling packet,or may include a combination thereof. In detail, the input IP packet andTS packet, and various types of data are encapsulated to be generated asthe ALP packet for transmission to each PLP, and the ALP packetcorresponds to an L2 packet in the ISO 7 layer model. However, the dataincluded in the payload is not limited to the aforementioned example,and the payload may include various types of data.

In addition, the signal processor 120 may signal-process the generatedpacket. In detail, the signal processor 120 signal-processes the packetto generate the transmission frame. Further, the signal processor 120may insert signaling information into a signaling area of the frame.Herein, the signaling information may be a layer 1 (L1) signaling signaltransmitting an L1 signal for frame synchronization, and a preamble intowhich the L1 signaling information is inserted may include an L1 presignaling area and an L1 post signaling area. Further, the L1 postsignaling area includes a configurable field and a dynamic field.

Although not illustrated, the signal processor 120 may perform functionscorresponding to bit interleaved and coded modulation (BICM) blocks12000 and 12000-1 and framing/interleaving blocks 13000 and 13000-1illustrated in FIGS. 3A to 3C.

The transmitter 130 may transmit the signal-processed frame to areceiving apparatus or receiver (not illustrated).

In detail, the transmitter 130 may perform functions corresponding tothe waveform generation blocks 14000 and 14000-1 illustrated in FIGS. 3Ato 3C. That is, the transmitter 130 performs modulation for modulatingthe generated frame to the RF signal, and transmits the RF signal to thereceiving apparatus or receiver.

Meanwhile, the base field configuring the header includes a first fieldset as a first value representing that the base field is a first lengthor a second value representing that the base field is a second length,and when the first field is set as the second value, the base field mayinclude a second field representing least significant bits (LSB) of apointer value representing a first value among respective start pointsof the input packets included in the payload and a third fieldrepresenting most significant bits (MSB) of the point value.

Further, a header of a packet may be divided into a base field, anoptional field, and an extension field according to a role thereof asillustrated in FIG. 8 described above, and the header necessarilyincludes a base field and whether the optional field is present may varyaccording to a value of a control value included in the base field.Further, whether the extension field is present may be selectedaccording to the value of the control field included in the optionalfield.

Here, the first field, the second field, and the third field may beincluded in the base field configuring the header.

In detail, this will be described in detail with reference to FIG. 17.

FIG. 17 is a diagram illustrating a structure of a packet according toanother exemplary embodiment.

Referring to FIG. 17, a packet 4000 includes a header 4100 and a payload4200 and a plurality of input packets 4201 may be mapped in the payload4200 of the packet 4000.

Here, like the first input packet among the plurality of input packets4201, one input packet is divided to be included in payloads ofdifferent packets. In addition, the base field may notify the startpoint of the input packet through the pointer value. Here, the pointervalue means an offset from the start point of the payload to the firststart point among the respective start points of the input packetsincluded in the payload.

In detail, a first field 4111 included in the base field of the header4100 may be set to a first value representing that the base field is afirst length, that is, 1 byte or a second value representing that thebase field is a second length, that is, 2 bytes.

Particularly, when the first field 4111 is set to the first value andthus the base field is 1 byte, the base field may include only thesecond field representing LSB of the pointer value representing thefirst value among respective start points of the input packets includedin the payload 4200, and as a result, the pointer value may representonly less than the predetermined value.

In addition, when the first field 4111 is set to the second value andthus the base field is 2 bytes, the base field may include the secondfield representing the LSB of the pointer value representing the firstvalue among respective start points of the input packets included in thepayload and the third field representing the MSB of the pointer value,and as a result, the pointer value may represent even greater than orequal to the predetermined value.

Here, the predetermined value may be 128 bytes, and as a result, whenthe first field 4111 is set to the first value, the pointer value mayrepresent only less than 128 bytes and when the first field 4111 is setto the second value, the pointer value may represent even greater thanor equal to 128 bytes.

For example, when any one input packet is disposed to be matched withthe start point of the payload 4200 of the packet 4000, and thus, thestart point of the corresponding input packet is the same as the startpoint of the payload, the pointer value representing the valuecorresponding to the start point of the corresponding input packet maybecome 0. That is, since the start point of the input packet may bedigitized and calculated based on the start point of the payload 4200,the pointer value representing the value corresponding to the startpoint of the corresponding input packet which starts the same as thestart point of the payload 4200 may become 0.

In addition, as illustrated in FIG. 17, when any one input packet isdivided to be included in the payload 4200 like the first input packetamong the plurality of input packets 4201, the start point of the firstinput packet is present in the previous packet and is not present in thecorresponding payload 4200, and thus, the first start point of therespective start points of the input packets included in the payload4200 immediately becomes a start point of the second input packet.Accordingly, the pointer value representing a value corresponding to thestart point of the second input packet may immediately become a valuecorresponding to a distance 4202 to the start point of the second inputpacket based on the start point of the payload 4200.

In addition, when the first field 4111 is set to the first value, thebase field of the header 4100 includes only a second field 4112representing the LSBs of the pointer value, and when the first field4111 is set to the second value, the base field of the header 4100 mayinclude the second field 4112 representing the LSBs of the pointer valueand a third field 4113 representing the MSBs of the pointer value.

Here, the first field 4111 may be the MODE field and the MODE field mayhave a size of 1 bit. In addition, when the MODE field is set to 0, thelength of the base field represents 1 byte, and when the MODE field isset to 1, the length of the base field may represent 2 bytes.

Further, the MODE field may represent whether the third field 4113representing the MSBs of the pointer value is present, and whether afourth field representing an extension mode of the header is present. Indetail, when the MODE field is set to 0, it is represented that the basefield includes only the second field 4112 representing the LSBs of thepointer value. Here, the second field 4112 may be the pointer (LSB)field representing the LSBs of the pointer value, and the pointer (LSB)field may have a size of 7 bits. Accordingly, when the MODE field is setto 0, the pointer value has no choice but to be represented up to lessthan 128 bytes, and the base field has the size of 1 byte including theMODE field (1 bit) and the pointer (LSB) field (7 bits).

Further, when the MODE field is set to 1, the base field may include thesecond field 4112 representing the LSBs of the pointer value and thethird field 4113 representing the MSBs of the pointer value. Here, thethird field 4113 representing the MSBs of the pointer value may be thepointer (MSB) field and the pointer (MSB) field may have a size of 6bits. Accordingly, when the MODE field is set to 1, the pointer valuemay be extended and represented up to 8191 bytes through a total of 13bits obtained by summing up the pointer (MSB) field (7 bits) and thepointer (MSB) field (6 bits), and the base field has a size of 2 bytesincluding the MODE field (1 bit), up the pointer (LSB) field (7 bits),the pointer (MSB) field (6 bits), and the fourth field (2 bits)representing the extension mode of the header 4100 to be describedbelow. As a result, the pointer (MSB) field and the fourth fieldrepresenting the extension mode of the header 4100 may be included inthe base field only when the MODE field is set to 1.

Accordingly, when the pointer value representing the first value amongthe start points of the input packets in the payload 4200 of the packet4000 is less than 128 bytes, the first field 4111, that is, the MODEfield is set to 0 and the base field includes the second field 4112,that is, only the pointer (LSB) field, and thus, the base field has thesize of 1 byte. When the pointer value representing the first valueamong the start points of the input packets in the payload 4200 of thepacket 4000 is equal to or greater than 128 bytes, the first field 4111,that is, the MODE field is set to 1 and the base field includes thesecond field 4112, that is, the pointer (LSB) field, the third field4113, that is, the pointer (MSB) field, and the fourth field, and thus,the base field has the size of total 2 bytes.

In addition, when the start point of the input packet in the payload4200 of the packet 4000 is not present, since the value corresponding tothe start point of the corresponding input packet may not be defined,the pointer value becomes 8191 and accordingly, the MODE field is set to1 and the base field has the size of 2 bytes.

Further, even when in the payload 4200 of the packet 4000, the inputpacket is not present and only the padding is present, the pointer valuebecomes 8191 and accordingly, the MODE field is set to 1 and the basefield has the size of 2 bytes.

FIG. 18 is a diagram illustrating a detailed configuration of the headerillustrated in FIG. 17, according to an exemplary embodiment. Referringto FIG. 18, as described above, the header 4100 includes a base field4110, and may further include an optional field 4120 and an extensionfield 4130, and whether a fourth field 4114 representing the extensionmode of the header 4100 to be described below is included may bedetermined.

In addition, as described above, when the first field 4111 is set to thefirst value, the base field 4110 includes only the second field 4112,and accordingly, it can be seen that the length of the base field 4110has the size of total 1 byte including 1 bit of the first field 4111 and7 bits of the second field 4112.

Further, as described above, when the first field 4111 is set to thesecond value, the base field 4110 includes the second field 4112, thethird field 4113, and the fourth field 4114 representing the extensionmode of the header 4110, and accordingly, it can be seen that the lengthof the base field 4110 has the size of total 2 bytes including 1 bit ofthe first field 4111, 7 bits of the second field 4112, 6 bits of thethird field 4113, and 2 bits of the fourth field 4114.

Meanwhile, when the first field 4111 is set to the second value, thebase field 4110 includes the fourth field 4114 representing theextension mode of the header 4110, and the fourth field 4114 may includeat least one of information about whether the optional field 4120 andthe extension field 4130 are present, the length of the optional field4120, and the structure of the extension field 4130.

In detail, the fourth field 4114 may be set to one of a third valuerepresenting that the optional field 4120 and the extension field 4130are not present, a fourth value representing that the optional field4120 is present and the length of the optional field 4120 is 1 byte, afifth value representing that the optional field 4120 is present and thelength of the optional field 4120 is 2 bytes, and a sixth valuerepresenting the optional field 4120 is present, the length of theoptional field 4120 is 2 bytes, and the extension field 4130 has astructure to include a plurality of extension payloads.

Here, the fourth field 4114 may be an OFI field and the OFI field mayhave a size of 2 bits. In detail, the information represented by valuesset in the OFI field may be summarized like in following Table 2.

TABLE 2 OFI Content 00 No Extension Mode: Optional field and extensionfield are not present. 01 Short Extension Mode: Optional field ispresent and length of optional field is 1 byte. 10 Long Extension Mode:Optional field is present and length of optional field is 2 bytes. 11Mixed Extension Mode: Structure in which optional field is present,length of optional field is 2 bytes, and extension field includes aplurality of extension payloads.

In detail, how the optional field 4130 and the extension field 4130 areincluded in the header 4100 according to the value set in the fourthfield 4114 will be described with reference to FIG. 19.

FIG. 19 is a diagram illustrating a detailed configuration of anoptional field according to another exemplary embodiment.

Referring to FIG. 19, when the fourth field is set to “00” which is thethird value, the header 4100 includes only the base field 4110 and doesnot include the optional field 4120 and the extension field 4120.

Further, when the fourth field is set to “01” which is the fourth value,as a short extension mode, the header 4100 may further include theoptional field 4120 having a size of 1 byte other than the base field4110. In addition, the presence or absence and the length of theextension field 4130 may be determined by fields included in theoptional field 4120.

In detail, the optional field 4120 may include a field 4121 (EXT_TYPEfield) representing a type of an extension payload 4131 included in theextension field 4130 and a field 4122 (EXT_LEN field) representing alength of the extension field 4130. Here, the EXT_TYPE field 4121 willbe defined as a fifth field and the EXT_LEN field 4122 will be definedas a sixth field.

Here, the EXT_TYPE field 4121 has a size of 3 bits and represents thetype of the extension payload 4131 included in the extension field 4130,and the detailed description thereof will be described below. Further,the EXT_LEN field 4122 has a size of 5 bits and may represent a lengthof the extension field 4130 in a range of 0 to 31 bytes.

When the EXT_LEN field 4122 is 0, the length of the extension field 4130is 0, and thus, the extension field 4130 is not present in the header4100.

In FIG. 19, it is illustrated that when the fourth field 4114 is set to“01” which is the fourth value, the EXT_LEN field 4122 included in theoptional field 4120 and the extension payload 4131 included in theextension field 4130 are separated from each other. However, in order todescribe that there is a case where the optional field 4120 has the sizeof 1 byte and there is a case where the optional field 4120 has the sizeof 2 bytes, the two fields are separated in the drawing. Actually, whenthe fourth field 4114 is set to “01” which is the fourth value, theoptional field 4120 has the size of 1 byte and thus, the extension field4130 is added subsequently to the optional field 4120. Accordingly, theEXT_LEN field 4122 included in the optional field 4120 and the extensionpayload 4131 included in the extension field 4130 are disposed next toeach other.

Further, when the fourth field 4114 is set to “10” which is the fifthvalue, as a long extension mode, the header 4100 may further include theoptional field 4120 having a size of 2 bytes other than the base field4110. In addition, the presence or absence and the length of theextension field 4130 may be determined by fields included in theoptional field 4120.

In detail, the optional field 4120 may include a field (EXT_TYPE field)4121 representing a type of the extension payload 4132 included in theextension field 4130, a field (EXT_LEN (LSB) field) 4123 representing anLSB part of a length of the extension field 4130, and a field (EXT_LEN(MSB) field) 4124 representing an MSB part of the length of theextension field 4130. Here, as described above, since the EXT_TYPE field4121 is defined as a fifth field and the field representing the lengthof the extension field 4130 is defined as a sixth field, the EXT_LEN(LSB) field 4123 may be defined to represent the LSB part of the sixthfield and the EXT_LEN (MSB) field 4124 may be defined to represent theMSB part of the sixth field.

Here, the EXT_TYPE field 4121 has a size of 3 bits and represents thetype of the extension payload 4132 included in the extension field 4130,and the detailed description thereof will be described below.

Further, the EXT_LEN (LSB) field 4123 may has a size of 5 bit of the LSBpart among total 13 bits for representing the length of the extensionfield 4130, and the EXT_LEN (MSB) field 4124 may have a size of 8 bitsof the MSB part among total 13 bits for representing the length of theextension field 4130. In addition, the field of total 13 bits connectingthe EXT_LEN (LSB) field 4123 and the EXT_LEN (MSB) field 4124 mayrepresent the length of the extension field 4130 in the entire lengthrange of the packet 4000 from 0.

Of course, when the field of total 13 bits connecting the EXT_LEN (LSB)field 4123 and the EXT_LEN (MSB) field 4124 is 0, the length of theextension field is 0, and thus, the extension field 4130 is not presentin the header 4100.

Further, when the fourth field is set to “11” which is the sixth value,as a mixed extension mode, the header 4100 may further include theoptional field 4120 having a size of 2 bytes other than the base field4110. In addition, the presence or absence and the length of theextension field 4130 and the structure of the extension field 4130 maybe determined by fields included in the optional field 4120.

In detail, the optional field 4120 may include a field (NUM_EXT field)4125 representing the number of a plurality of extension payloads 4133included in the extension field 4130, a field (EXT_LEN(LSB) field) 4126representing the LSB part of the length of the extension field 4130, anda field (EXT_LEN (MSB) field) 4127 representing the MSB part of thelength of the extension field 4130.

Here, the NUM_EXT field 4125 has a size of 3 bits and may represent thenumber of the plurality of extension payloads 4133 other than paddingincluded in the extension field 4130.

Particularly, the extension field 4130 may indicate presence of two toseven extension payloads, and the detailed structure thereof will bedescribed with reference to FIG. 25.

Further, the EXT_LEN (LSB) field 4126 may has a size of 5 bits of theLSB part among total 13 bits for representing the length of theextension field 4130, and the EXT_LEN (MSB) field 4127 may have a sizeof 8 bits of the MSB part among total 13 bits for representing thelength of the extension field 4130.

Meanwhile, the length of the extension field 4130 which may berepresented by the field of total 13 bits connecting the EXT_LEN (LSB)field 4126 and the EXT_LEN (MSB) field 4127 will be described togetherwhile describing the structure of the extension field 4130.

FIG. 25 is a diagram illustrating a structure of the extension fieldaccording to an exemplary embodiment.

When the fourth field 4114 is set to the sixth value, the extensionfield 4130 may include a plurality of fields representing respectivetypes of the plurality of extension payloads and a plurality of fieldsrepresenting respective lengths of the plurality of extension payloads.

In detail, referring to FIG. 25, when the fourth field 4114 is set tothe sixth value, that is, “11”, this means a mixed extension mode, andaccordingly, the extension field 4130 may include the plurality ofextension payloads Extension payload 1 (4145), . . . , Extension payloadN (4146). In this case, the extension field 4130 may include a pluralityof fields EXT_TYPE 1 (4141), . . . , EXT_TYPE N (4143) representingrespective types of the plurality of extension payloads Extensionpayload 1 (4145), . . . , Extension payload N (4146) and a plurality offields EXT_LEN 1 field (4142), . . . , EXT_LEN N field (4144)representing respective lengths of the plurality of extension payloadsExtension payload 1 (4145), . . . , Extension payload N (4146). Here, asdescribed above, since the extension field 4130 may include two to sevenextension payloads, a range of N may become from 2 to 7.

The plurality of extension payloads (Extension payload 1 (4145), . . . ,Extension payload N (4146)) all do not include the padding.

Further, when one extension payload is included in the extension field4130, one EXT_TYPE field representing the type of the correspondingextension payload and one EXT_LEN field are included in the extensionfield 4130. Here, when considering that the EXT_TYPE field has the sizeof 3 bits and the EXT_LEN field has the size of 13 bits, a header havingthe size of total 2 bytes with respect to the one extension payload isincluded in the extension field 4130. Here, the header includes theEXT_TYPE field and the EXT_LEN field, and will be defined by the genericterm of fields disposed at the front end of the extension field 4130.

Accordingly, when N extension payloads are included in the extensionfield 4130, the extension field 4130 includes a header having a size oftotal 2N bytes including a plurality of EXT_TYPE fields associated withthe respective extension payloads and an EXT_LEN field.

As described above, the extension field 4130 may include at least twoextension payloads and as a result, may include a header having a sizeof 4 bytes. However, when the value of the EXT_LEN field is 0, it can beseen that there is no extension payload, and in this case, the length ofthe extension field 4130 may have no choice but to be at least 4 bytes.

As a result, the length of the extension field 4130 which may berepresented by the field of total 13 bits connecting the EXT_LEN (LSB)field 4126 and the EXT_LEN (MSB) field 4127 described in FIG. 19 mayrepresent the length of the extension field 4130 in a range of theentire length of the packet 4000 from 4 bytes.

Each of EXT_LEN 1 field (4142), . . . , EXT_LEN N field (4144)illustrated in FIG. 25 may include the EXT_LEN (LSB) field having a sizeof 5 bits and the EXT_LEN (MSB) field having a size of 8 bits.Accordingly, one header having a size of 2 bytes for one extensionpayload includes an EXT_TYPE field having a size of 3 bits, an EXT_LEN(LSB) field having a size of 5 bits, and an EXT_LEN (MSB) field having asize of 8 bits.

Further, in the extension field 4130, when the fourth field 4114 is setto one of the fourth value and the fifth value, the length of theextension payload included in the extension field 4130 is smaller thanthe length of the extension field 4130, the extension payload isincluded in the extension field 4130 and the padding may be included inthe remaining part.

For example, in FIG. 19, when the fourth field 4114 is set to “01” whichis the fourth value and an actual length of the extension payload 4131included in the extension field 4130 is smaller than the length of theextension field 4130 defined by the EXT_LEN field 4122, the extensionfield 4130 includes the extension payload 4131 and the padding may beincluded in the remaining part of the extension field 4130. Here, thepadding means meaningless data, and the meaningless data may be randomlydetermined by various methods according to a system design. Further, thepadding is not required to be filled only with 0, may be filled onlywith 1, and may be filled with a meaningless combination of 0 and 1.However, a case where the padding according to the exemplary embodimentis filled only with 0 will be described as an example.

Further, for example, in FIG. 19, when the fourth field 4114 is set to“10” which is the fifth value and an actual length of the extensionpayload 4132 included in the extension field 4123 is smaller than thelength of the extension field 4130 defined by the EXT_LEN (LSB) field4123 and the EXT_LEN (MSB) field 4124, the extension field 4130 includesthe extension payload 4132 and the padding may be included in theremaining part of the extension field 4130.

Meanwhile, in the extension field 4130, when the fourth field 4114 isset to the sixth value, the plurality of extension payloads are includedin the extension field 4130 and the padding may be included in theremaining part.

For example, referring to FIG. 25, when the fourth field 4114 is set to“11” which is the sixth value, in the case where a total actual lengthof the plurality of fields EXT_TYPE 1 (4141), . . . , EXT_TYPE N (4143)representing the respective types of the plurality of extension payloadsExtension payload 1 (4145), . . . , Extension payload N (4146) includedin the extension field 4130, the plurality of fields EXT_LEN 1 field(4142), . . . , EXT_LEN N field (4144) representing the respectivelengths of the plurality of extension payloads Extension payload 1(4145), . . . , Extension payload N (4146), and the plurality ofpayloads Extension payload 1 (4145), . . . , Extension payload N (4146)is smaller than the length of the extension field 4130 defined by theEXT_LEN (LSB) field 4126 and the EXT_LEN (MSB) field 4127, the extensionfield 4130 includes the plurality of fields EXT_TYPE 1 (4141), . . . ,EXT_TYPE N (4143) representing the respective types of the plurality ofextension payloads, the plurality of fields EXT_LEN 1 field (4142), . .. , EXT_LEN N field (4144) representing the respective lengths of theplurality of extension payloads, and the plurality of payloads Extensionpayload 1 (4145), . . . , Extension payload N (4146) and the padding maybe included in the remaining part.

Meanwhile, how the structure of the packet 4000 is entirely changedaccording to the values set in the first field 4111 and the fourth field4114 will be described with reference to FIGS. 20 to 24.

FIGS. 20 to 24 are diagrams illustrating structures of a packetaccording to various exemplary embodiments.

Referring to FIG. 20, when the first field 4111 is set to the firstvalue, the base field 4110 includes only the second field 4112representing the LSBs of the pointer value, and the optional field 4120and the extension field 4130 are not included in the packet 4000, and asa result, the packet 4000 includes the base field 4110 having a size of1 byte and the payload 4200.

Referring to FIG. 21, when the first field 4111 is set to the secondvalue, the base field 4110 includes a second field 4112 representing theLSBs of the pointer value and a third field 4113 representing the MSBsof the pointer value, and may additionally include a fourth field 4114representing an extension mode of the header 4100.

Accordingly, the packet 4000 includes the base field 4110 having thelength of 2 bytes. However, in FIG. 21, since the fourth field 4114 isset to the third value, that is, “00”, the optional field 4120 and theextension field 4130 are not included in the packet 4000, and as aresult, the packet 4000 includes the base field 4110 having a size of 2bytes and the payload 4200.

Referring to FIG. 22, when the first field 4111 is set to the secondvalue, the base field 4110 includes a second field 4112 representing theLSBs of the pointer value and a third field 4113 representing the MSBsof the pointer value, and may additionally include a fourth field 4114representing an extension mode of the header 4100.

Accordingly, the packet 4000 includes the base field 4110 having thelength of 2 bytes. However, in FIG. 22, since the fourth field 4114 isset to the fourth value, that is, “01”, the optional field 4120 having asize of 1 byte and the extension field 4130 having a size of 1 to 31bytes are included in the packet 4000. As a result, the packet 4000includes the base field 4110 having the size of 2 bytes, the optionalfield 4120 having the size of 1 byte, the extension field 4130 havingthe size of 1 to 31 bytes, and the payload 4200. Further, the optionalfield 4120 may include an EXT_TYPE field 4121 and an EXT_LEN field 4122.

Referring to FIG. 23, when the first field 4111 is set to the secondvalue, the base field 4110 includes a second field 4112 representing theLSBs of the pointer value and a third field 4113 representing the MSBsof the pointer value, and may additionally include a fourth field 4114representing an extension mode of the header 4100.

Accordingly, the packet 4000 includes the base field 4110 having thelength of 2 bytes. However, in FIG. 23, since the fourth field 4114 isset to the fifth value, that is, “10”, the optional field 4120 having asize of 2 bytes and the extension field 4130 are included in the packet4000. Here, the length of the extension field 4130 may be defined by theEXT_LEN (LSB) field 4123 and the EXT_LEN (MSB) field 4124 included inthe optional field 4120 and may be from 0 to 2¹³−1 bytes. Further, theoptional field 4120 may include the EXT_TYPE field 4121, the EXT_LEN(LSB) field 4123, and the EXT_LEN (MSB) field 4124.

Referring to FIG. 24, when the first field 4111 is set to the secondvalue, the base field 4110 includes a second field 4112 representing theLSBs of the pointer value and a third field 4113 representing the MSBsof the pointer value, and may additionally include a fourth field 4114representing an extension mode of the header 4100.

Accordingly, the packet 4000 includes the base header 4110 having thelength of 2 bytes. However, in FIG. 24, since the fourth field 4114 isset to the sixth value, that is, “11”, the optional field 4120 having asize of 2 bytes and the extension field 4130 are included in the packet4000. Here, the length of the extension field 4130 may be defined by theEXT_LEN (LSB) field 4126 and the EXT_LEN (MSB) field 4127 included inthe optional field 4127 and may be from 0 to 2¹³−1 bytes. Further, theoptional field 4120 may include the NUM_EXT field 4125, the EXT_LEN(LSB) field 4126, and the EXT_LEN (MSB) field 4127. In addition, theextension field 4130 may include the plurality of extension payloads,and the detailed description thereof is described in FIG. 25 in advanceand will be omitted.

The EXT_TYPE field 4121 included in the optional field 4120 representstypes of the extension payloads 4131 and 4132 included in the extensionfield 4130, and may be used to perform various functions according tothe predetermined value. For example, different information according tothe value set in the EXT_TYPE field is illustrated like the followingTable 3.

TABLE 3 EXT_TYPE Description 000 Counter 001-110 These fields arereserved for future extension types 111 Padding All bytes of extensionfield are padded with 0x00

In detail, when the EXT_TYPE field 4121 is set to “000”, a counterfunction may be performed, and in detail, a predetermined field having asize by a value included in the EXT_LEN field may be included in theextension field 4130 as an extension payload. Here, the predeterminedfield may perform a function of numbering and identifying a plurality ofpackets included in a current PLP one by one and the counter value maybe linearly increased from 0.

For example, when the fourth field 4114 is set to the fourth value, thatis, “01” and the EXT_LEN field includes the value of 1, thepredetermined field has the size of 1 byte and as a result, the countervalue may have values of 0 to 255.

Here, the predetermined field performing the counter function may beindependently used with respect to each PLP, and when the counter valuereaches a maximum value, the counter value of the next packet is resetto 0 and increased again.

Further, with respect to the PLP to which channel bonding is applied, asingle counter, that is, a single predetermined field may be used forincreasing a counter value in the packet, and this may be performedbefore the packet is assigned to a specific RF channel.

The aforementioned content may be applied even to EXT_TYPE 1 (4141), . .. , EXT_TYPE N (4143) included in the extension field 4130 when thefourth field 4114 is set to the sixth value, that is, “11”.

When the fourth field 4114 is set to one of the fourth value, that is,“01” and the fifth value, that is, “10” and the EXT_TYPE field 4121 isset to “111”, all of the extension fields 4130 are filled with padding.

In detail, when the first field 4114 is set to the fourth value, thatis, “01” or the fifth value, that is, “10”, the optional field 4120further includes a fifth field representing the type of extensionpayload included in the extension field 4130, that is, the EXT_TYPEfield 4121 and a sixth field representing the length of the extensionfield 4130 (which means the EXT_LEN field 4122 when the fourth field4114 is the fourth value and the EXT_LEN(LSB) field 4123 and the EXT_LEN(MSB) field 4124 when the fourth field 4114 is the fifth value), andwhen the fifth field, that is, the EXT_TYPE field 4121 is set to thepredetermined value, the extension field 4130 may be completely filledby padding.

For example, when the fifth field, that is, the EXT_TYPE field 4121 isset to “111”, this means that the extension field 4130 is completelyfilled by padding as defined in Table 3, and as a result, the extensionfield 4130 is completely filled by padding.

For example, in the case where the fourth field 4114 is set to thefourth value, that is, “01” and the EXT_LEN field 4122 includes a valuerepresenting that the length of the extension field 4130 is 0 byte, ascompared with a case where the fourth field 4114 is set to the thirdvalue, that is, “00”, padding of 1 byte is included in the header 4100.That is, the optional field 4120 of 1 byte serves as the padding of 1byte.

Further, in the case where the fourth field 4114 is set to the fifthvalue, that is, “10” and the EXT_LEN (LSB) field 4123 and the EXT_LEN(MSB) field 4124 include a value representing that the length of theextension field 4130 is 0 byte, as compared with a case where the fourthfield 4114 is set to the third value, that is, “00”, padding of 2 bytesis included in the header 4100. That is, the optional field 4120 of 2bytes serves as the padding of 2 byte.

When the fourth field 4114 is set to the sixth value, that is, “11”, asdescribed above, the extension field 4130 is filled with a plurality ofextension payloads and the remaining part may be filled with thepadding. In this case, it is not required that EXT_TYPE 1 (4141), . . ., EXT_TYPE N (4143) are separately set to “111”.

FIG. 26A is a block diagram illustrating a configuration of a receivingapparatus according to an exemplary embodiment.

Referring to FIG. 26A, the receiving apparatus 200 includes a receiver210, an information extractor 220, and a signal processor 220.

The receiving apparatus 200 may be implemented to receive data a thetransmitting apparatus mapping and transmitting data included in aninput stream on at least one signal processing path.

The receiver 210 may receive the input stream including a packetincluding a header and a payload. That is, the receiver 210 receives atransmission frame including the data mapped on at least one signalprocessing path. In detail, the receiver 210 may receive signalinginformation and the stream including the data mapped on at least onesignal processing path. Here, the signaling information may includeinformation about an input type of the input stream input to thereceiving apparatus and information about a data type mapped on at leastone signal processing path. Here, the information about the input typeof the input stream may represent whether all of the signal processingpaths in the frame are the same input type. In addition, the detailedinformation included in the signaling information is described above andthe detailed description will be omitted.

The information extractor 220 extracts the header from the packet andmay extract information representing the start point of a data packet inthe payload and information about whether an additional field is presentfrom the extracted header.

With respect to the information representing the start point of the datapacket in the payload included in the header and the information aboutwhether the additional field is present, the part for the transmittingapparatus 100 is described in advance and the detailed description willbe omitted.

The signal processor 230 may signal-process the data packet included inthe payload based on the information representing the start point of theextracted data packet and the information about whether an additionalfield is present. That is, the start point of the data packet in thepayload is accurately detected based on the information representing thestart point of the data packet and decoding may be performed from thestart point of the data packet. Further, the signal processor 230 maydetermine whether the received packet includes an optional field and anextension field based on the information about whether the additionalfield is present and detect information required for signal-processingthe data packet from the optional field and the extension field.

Here, the information representing the start point of the data packetmay include information about whether an MSB part is present accordingto a distance between the start point of the payload and the start pointof the data packet.

Further, the information about whether the additional field is presentmay include information representing whether at least one of theoptional field and the extension field is present and the length of theoptional field and the extension field.

Further, the optional field may include information representing whetherat least one of the optional field and the extension field includespadding.

Further, the signal processor 230 extracts signaling information fromthe received frame. Particularly, the signal processor 230 extracts anddecodes L1 signaling to obtain various information about a correspondingPLP included in an L1 pre signaling area and an L1 post signaling area.Further, the signal processor 230 may signal-process the frame based onthe extracted signaling information. For example, the signal processingmay perform demodulation, frame de-building, BICM decoding, and inputde-processing.

In detail, the signal processor 230 generates a baseband packet bysignal-processing the frame received through the receiver 210 andextracts header information from the generated baseband packet.

In addition, the signal processor 230 may restore the stream, that is,the input stream initially input to the aforementioned transmittingapparatus 100 by signal-processing the payload data included in thebaseband packet based on the extracted header information.

Meanwhile, a receiving apparatus 200 according to another exemplaryembodiment includes a receiver 210, an information extractor 220, and asignal processor 230, the receiver 210 includes a packet including aheader and a payload, the information extractor 220 may extract theheader from the packet and extract information included in the header,and the signal processor 230 may signal-process the input packetincluded in the payload based on the extracted information. Here, thedetailed description for the receiver 210, the information extractor220, and the signal processor 230 is described above and the detaileddescription will be omitted.

Further, the header includes a first field set to a first valuerepresenting that a pointer value indicating a first start point amongthe respective start points of the input packets included in the payloadis less than the predetermined value or a second value representing thatthe pointer value is equal to or greater than the predetermined value.When the first field is set to the second value, the header may includea second field representing the LSBs of the pointer value and a thirdfield representing the MSBs of the pointer value.

FIG. 26B is a block diagram provided to explain in detail a signalprocessor according to an exemplary embodiment.

Referring to FIG. 26B, the signal processor 230 includes a demodulator231, a decoder 232 and a stream generator 233.

The demodulator 231 performs demodulation according to OFDM parametersfrom the received RF signals, performs sync-detection, and recognizeswhether a currently received frame includes necessary service data whenthe sync is detected from signaling information stored in a sync area.For example, the demodulator 221 may recognize whether a mobile frame isreceived or a fixed frame is received.

In this case, if OFDM parameters are not previously determined regardinga signaling area and a data area, the demodulator 221 may performdemodulation by obtaining OFDM parameters regarding the signaling areaand the data area stored in the sync area, and obtaining informationabout OFDM parameters regarding the signaling area and the data areawhich are disposed right after the sync area.

The decoder 232 performs decoding of necessary data. In this case, thedecoder 232 may perform decoding by obtaining parameters of an FECmethod and a modulating method regarding the data stored in each dataarea based on the signaling information. Further, the decoder 232 maycalculate positions of necessary data based on the data informationincluded in a configurable field and a dynamic field. Thus, it maycalculate which positions of the frame a requested PLP is transmitted.

The stream generator 233 may generate data to be served by processing abaseband packet input from the decoder 232.

For example, the stream generator 233 may generate an ALP packet fromthe baseband packet in which errors are corrected based on an ISSY mode,buffer size (BUFS), time to output (TTO) values and input stream clockreference (ISCR) values.

Specifically, the stream generator 233 may include de-jitter buffers.The de-jitter buffers may regenerate correct timing to restore an outputstream based on the ISSY mode, BUFS, TTO values and ISCR values.Thereby, a delay for sync between a plurality of PLPs can becompensated.

FIG. 27 is a block diagram of a receiving apparatus according to anexemplary embodiment.

Referring to FIG. 27, the receiving apparatus 4400 may include acontroller 4410, an RF receiver 4420, a demodulator 4430, and a serviceplayer 4440.

The controller 4410 determines an RF channel and a PLP in which aselected service is transmitted. At this process, the RF channel may bedefined by a center frequency and a bandwidth, and the PLP may bedefined by a PLP identifier (ID). Certain services may be transmittedthrough more than one PLP belonging to more than one RF channel percomponent constituting services. However, it is assumed in the followingdescriptions that all data required for playing one service aretransmitted through one PLP with one RF channel for convenientexplanation. Thus, services are provided with a unique data obtainingpath to play services, and the data obtaining path is specified by an RFchannel and a PLP.

The RF receiver 4420 extracts RF signals from a selected RF channel bythe controller 4410, and delivers OFDM symbols, extracted by performingsignal-processing of the RF signals, to the demodulator 4430. The signalprocessing may include synchronization, channel estimation andequalization. Information required for the signal processing ispredetermined between a transmitting apparatus and the receivingapparatuses or transmitted to the receiving apparatus in a predeterminedOFDM symbols among the OFDM symbols.

The demodulator 4430 extracts a user packet by performing signalprocessing of the OFDM symbols, and delivers to the service player 4440.The service player 4440 plays and outputs the service selected by a userwith the user packet. A format of the user packet may be differentaccording to implementing services. For example, a TS packet or an IPv4packet may be the user packet.

FIG. 28 is a block diagram describing the demodulator of FIG. 27according to an exemplary embodiment.

Referring to FIG. 28, the demodulator 4430 may include a frame demapper4431, a BICM decoder 4432 for L1 signaling, a controller 4433, a BICMdecoder 4434, and an output processor 4435.

The frame demapper 4431 selects OFDM cells constituting FEC blocksbelonging to a selected PLP from a frame constituted with OFDM symbolsbased on controlling information delivered from the controller 4433, anddelivers to the decoder 4434. Further, the frame demapper 4431 selectsOFDM cells corresponding to more than one FEC block included in the L1signaling, and delivers to BICM decoder 4432 for the L1 signaling.

The BICM decoder 4432 for the L1 signaling signal-processes the OFDMcells corresponding to the FEC blocks belonging to the L1 signaling,extracts L1 signaling bits, and delivers to the controller 4433. In thiscase, the signal processing may include extracting log-likelihood ratio(LLR) values for decoding low density parity check (LDPC) codes in OFDMcells, and decoding the LDPC codes by using the extracted LLR values.

The controller 4433 extracts an L1 signaling table from the L1 signalingbits, and controls operations of the frame demapper 4431, the BICMdecoder 4434, and the output processor 4435 by using values of the L1signaling table. FIG. 37 illustrates that the BICM decoder 4432 for theL1 signaling does not use controlling information of the controller 4433for convenient explanation. However, if the L1 signaling includes alayer structure similar to the L1 pre-signaling and the L1post-signaling described above, the BICM decoder 4432 for the L1signaling may be constituted with more than one BICM decoding block, andoperations of the BICM decoding blocks and the frame demapper 4431 maybe controlled based on upper-layer L1 signaling information, as clearlyunderstood in the above description.

The BICM decoder 4434 signal-processes the OFDM cells constituting FECblocks belonging to the selected PLP, extracts baseband packets, anddelivers the baseband packets to the output processor 4435. The signalprocessing may include extracting LLR values for coding and decodingLDPC codes in OFDM cells, and decoding the LDPC codes by using theextracted LLR values. These two operations may be performed based on thecontrolling information delivered from the controller 4433.

The output processor 4435 signal-processes the baseband packets,extracts a user packet, and delivers the extracted user packet to theservice player. In this case, the signal processing may be performed onthe controlling information delivered from the controller 4433.

Meanwhile, according to an exemplary embodiment, the output processor1235 may include an ALP packet processor (not illustrated) whichextracts an ALP packet from a baseband packet.

FIG. 29 is a flowchart provided to briefly explain an operation of areceiving apparatus from a time point when a user selects a service to atime point when the selected service is played.

It is assumed that service information about all the services that canbe selected at an initial scan process of S4600 is obtained prior to aservice select process at S4610. The service information may includeinformation about an RF channel and a PLP which transmits data requiredfor playing a specific service in a current broadcasting system. Oneexample of the service information may be Program-SpecificInformation/Service Information (PSI/SI) of an MPEG-2 TS, which may beusually obtained through L2 signaling and an upper layer signaling.

When a user selects a service at S4610, the receiving apparatus modifiesa frequency transmitting the selected service at S4620, and performsextracting RF signals at S4630. While performing S4620 modifying thefrequency transmitting the selected service, the service information maybe used.

When the RF signals are extracted, the receiver performs S4640extracting L1 signaling from the extracted RF signals. The receivingapparatus selects the PLP transmitting the selected service by using theextracted L1 signaling at S4650, and extracts baseband packets from theselected PLP at S4660. At S4650 selecting the PLP transmitting theselected service, the service information may be used.

Further, S4660 extracting the baseband packets may include selectingOFDM cells belonging to the PLP by demapping a transmission frame,extracting LLR values for coding/decoding LDPC, and decoding LDPC codesby using the extracted LLR values.

The receiving apparatus performs S4670 extracting an ALP packet from theextracted baseband packet by using header information about theextracted baseband packet, and performs S4680 extracting a user packetfrom the extracted ALP packet by using header information about theextracted baseband packet. The extracted user packet is used in S1690playing the selected service. At S4670 extracting the ALP packet and atS4680 extracting the user packet, L1 signaling information obtained atS4640 extracting the L1 signaling may be used. In this case, a processof extracting the user packet from the ALP packet (restoring null TSpacket and inserting a TS sync byte) is the same as described above.According to the exemplary embodiments as described above, various typesof data may be mapped to a transmittable physical layer and dataprocessing efficiency may be improved.

FIG. 30 is a flowchart illustrating a controlling method of atransmitting apparatus according to an exemplary embodiment.

In the controlling method of the transmitting apparatus illustrated inFIG. 30, a packet including a header and a payload is generated based onan input packet (S3510).

In addition, the generated packet is signal-processed (S3520).

Thereafter, the signal-processed packet is transmitted (S3530).

Here, the base field configuring the header includes a first field setas a first value representing that the base field is a first length or asecond value representing that the base field is a second length, andwhen the first field is set as the second value, the base field mayinclude a second field representing LSB of a pointer value representinga first value among respective start points of the input packetsincluded in the payload and a third field representing MSB of the pointvalue.

Further, when the first field, the second field, and the third field areincluded in the base field configuring the header, the base field mayinclude a fourth field representing an extension mode of the header.

Further, the fourth field may include at least one of information aboutwhether the optional field is present, a length of the optional field,and a structure of the extension field.

Further, the fourth field may be set to one of a third valuerepresenting that the optional field and the extension field are notpresent, a fourth value representing that the optional field is presentand a length of the optional field is 1 byte, a fifth value representingthat the optional field is present and the length of the optional fieldis 2 bytes, and a sixth value representing the optional field ispresent, the length of the optional field is 2 bytes, and the extensionfield has a structure to include a plurality of extension payloads.

Further, when the first field is set to the fourth value or the fifthvalue, the optional field further includes a fifth field representing atype of the extension payload included in the extension field and asixth field representing the length of the extension field, and when thefifth field is set to the predetermined value, the extension field maybe completely filled by padding.

Further, when the fourth field is set to the fifth value, the optionalfield may include a field representing a type of extension payloadincluded in the extension field, a field representing an LSB part of thelength of the extension field, and a field representing an MSB part ofthe length of the extension field.

Further, when the fourth field is set to the sixth value, the optionalfield may include a field representing the number of a plurality ofextension payloads included in the extension field, a field representingan LSB part of the length of the extension field, and a fieldrepresenting an MSB part of the length of the extension field.

Here, the extension field may include a plurality of field representingrespective types of the plurality of extension payloads and a pluralityof fields representing respective lengths of the plurality of extensionpayloads.

Further, the extension field may include an extension payload and theremaining part may include padding, when the fourth field is set to oneof the fourth value and the fifth value and the length of the extensionpayload included in the extension field is smaller than the length ofthe extension field.

Further, the extension field may include a plurality of extensionpayloads and the remaining part may include padding when the fourthfield is set to the sixth value.

Meanwhile, in a controlling method of the transmitting apparatusaccording to another exemplary embodiment, a packet including a headerincluding a base header in which information about a start point of adata packet in a payload and information about whether an additionalfield is present are included, and the payload is generated.

Here, the information about the start point of the data packet mayinclude information about whether an MSB part is present according to adistance between the start point of the payload and the start point ofthe data packet.

Further, the information about the start point of the data packet mayinclude one of a first value representing that the MSB part is notpresent and a second value representing that the MSB part is present.

Further, the information about whether the additional field is presentmay include information representing whether at least one of theoptional field and the extension field is present and the length of theoptional field and the extension field.

Here, the optional field may include information representing whether atleast one of the optional field and the extension field includespadding.

Further, the information about whether the additional field is presentmay include one of a first value representing that the optional fieldand the extension field are not present, a second value representingthat the optional field is present, the extension field is not present,and a length of the optional field is 1 byte, a third value representingthat the optional field is present, the extension field is not present,and the length of the optional field is 2 bytes, and a fourth valuerepresenting that the optional field and the extension field are presentand the length of the optional field and the extension field exceeds 2bytes.

Further, the optional field may include information representing thelength of the extension field when the information about whether theadditional field is present is set to the fourth value.

Further, the information representing the length of the extension fieldmay include at least one of the LSB part and the MSB part according tothe length of the extension field.

In addition, the generated frame is signal-processed.

Thereafter, the signal-processed frame is transmitted.

Meanwhile, FIG. 31 is a flowchart for describing a controlling method ofa receiving apparatus according to an exemplary embodiment.

In the controlling method of the receiving apparatus illustrated in FIG.31, a stream including a packet including a header and a payload isreceived (S3610).

In addition, the header is extracted from the packet and informationincluded in the header is extracted (S3620).

Thereafter, an input packet included in the payload is signal-processedbased on the extracted information (S3630).

Here, the base field configuring the header includes a first field setas a first value representing that the base field is a first length or asecond value representing that the base field is a second length, andwhen the first field is set as the second value, the base field mayinclude a second field representing LSB of a pointer value representinga first value among respective start points of the input packetsincluded in the payload and a third field representing MSB of the pointvalue.

Meanwhile, in a controlling method of a receiving apparatus according toanother exemplary embodiment, a stream including a packet in which aheader and a payload are included is received.

In addition, the header is extracted from the packet, and informationrepresenting a start point of a data packet in the payload andinformation about whether an additional field is present are extractedfrom the extracted header.

In addition, the data packet included in the payload is signal-processedbased on the information about the start point of the extracted datapacket and the information about whether an additional field is present.

Here, the information about the start point of the data packet mayinclude information about whether an MSB part is present according to adistance between the start point of the payload and the start point ofthe data packet.

Further, the information about whether the additional field is presentmay include information about whether at least one of the optional fieldand the extension field is present and the length of the optional fieldand the extension field.

Further, the optional field may include information about whether atleast one of the optional field and the extension field includes apadding.

As described above, according to the exemplary embodiments, varioustypes of data can be mapped to a transmittable physical layer and dataprocessing efficiency can be improved.

Meanwhile, a non-transitory computer readable medium in which programssequentially performing the signal processing method according to theabove exemplary embodiments are stored may be provided.

As an example, a non-transitory computer readable medium in whichprograms performing generating a packet including a header and a payloadbased on at least one input packet, signal-processing the generatedpacket, and transmitting the signal-processed packet are stored may beprovided.

Further, as an example, a non-transitory computer readable medium inwhich programs performing receiving a stream including a packetincluding a header and a payload, extracting the header from the packetand extracting information included in the header, and signal-processingan input packet included in the payload based on the extractedinformation are stored may be provided.

The non-transitory computer readable medium means a medium whichsemi-permanently stores the data and is readable by a correspondingapparatus, but a medium which stores the data for a short time, such asa register, a cache, and a memory. In detail, various aforementionedapplications or programs may be stored and provided in thenon-transitory computer readable medium such as a compact disc (CD), adigital versatile disk (DVD), a hard disk, a Blu-ray disk, a universalserial bus (USB), a memory card, and a read-only memory (ROM) not beinglimited thereto.

At least one of the components, elements, modules or units representedby a block as illustrated in the drawings such as FIGS. 6, 7A, 8, 26A,26B, 27 and 28 may be embodied as various numbers of hardware, softwareand/or firmware structures that execute respective functions describedabove, according to an exemplary embodiment. For example, at least oneof these components, elements or units may use a direct circuitstructure, such as a memory, processing, logic, a look-up table, etc.that may execute the respective functions through controls of one ormore microprocessors or other control apparatuses. Also, at least one ofthese components, elements or units may be specifically embodied by amodule, a program, or a part of code, which contains one or moreexecutable instructions for performing specified logic functions, andexecuted by one or more microprocessors or other control apparatuses.Also, at least one of these components, elements or units may furtherinclude a processor such as a central processing unit (CPU) thatperforms the respective functions, a microprocessor, or the like. Two ormore of these components, elements or units may be combined into onesingle component, element or unit which performs all operations orfunctions of the combined two or more components, elements of units.Also, at least part of functions of at least one of these components,elements or units may be performed by another of these components,element or units. Further, although a bus is not illustrated in theabove block diagrams, communication between the components, elements orunits may be performed through the bus. Functional aspects of the aboveexemplary embodiments may be implemented in algorithms that execute onone or more processors. Furthermore, the components, elements or unitsrepresented by a block or processing steps may employ any number ofrelated art techniques for electronics configuration, signal processingand/or control, data processing and the like.

Meanwhile, the detailed exemplary embodiments have been described thusfar, but various modifications can be made without departing from thescope of the inventive concept. Therefore, the inventive concept shouldnot be limited to the exemplary embodiment and should be defined by theappended claims and equivalents to the appended claims.

What is claimed is:
 1. A transmitting apparatus comprising: at least one processor configured to implement a packet generator which generates a packet comprising a header and a payload based on a plurality of input packets, and a signal processor which signal-processes the generated packet; and a transmitter configured to transmit the signal-processed packet, wherein a base field included in the header comprises a first field set to a first value representing that the base field is a first length or a second value representing that the base field is a second length, and wherein, when the first field is set to the second value, the base field comprises a second field representing least significant bits (LSB) of the pointer value indicating a first start point among respective start points of the input packets included in the payload and a third field representing most significant bits (MSB) of the pointer value.
 2. The transmitting apparatus of claim 1, wherein the base field comprises a fourth field representing an extension mode of the header, and the fourth field comprises at least one of information about whether an optional field is present, a length of the optional field, and a structure of an extension field.
 3. The transmitting apparatus of claim 2, wherein the fourth field is set to one of a third value representing that the optional field and the extension field are not present, a fourth value representing that the optional field is present and a length of the optional field is 1 byte, a fifth value representing that the optional field is present and the length of the optional field is 2 bytes, and a sixth value representing the optional field is present, the length of the optional field is 2 bytes, and the extension field has a structure comprising a plurality of extension payloads.
 4. The transmitting apparatus of claim 3, wherein when the fourth field is set to the fourth value or the fifth value, the optional field further comprises a fifth field representing a type of extension payload included in the extension field and a sixth field representing a length of the extension field, and when the fifth field is set to predetermined value, the extension field is completely filled padding.
 5. The transmitting apparatus of claim 3, wherein when the fourth field is set to the fifth value, the optional field comprises a field representing a type of an extension payload included in the extension field, a field representing an LSB part of a length of the extension field, and a field representing an MSB part of the length of the extension field.
 6. The transmitting apparatus of claim 3, wherein when the fourth field is set to the sixth value, the optional field comprises a field representing a number of a plurality of extension payloads included in the extension field, a field representing an LSB part of a length of the extension field, and a field representing an MSB part of the length of the extension field.
 7. The transmitting apparatus of claim 6, wherein the extension field comprises a plurality of fields representing respective types of the plurality of extension payloads and a plurality of fields representing respective lengths of the plurality of extension payloads.
 8. The transmitting apparatus of claim 7, wherein, when the fourth field is set to one of a fourth value and a fifth value and a length of an extension payload included in the extension field is smaller than a length of the extension field, the extension field comprises the extension payload and padding.
 9. The transmitting apparatus of claim 3, wherein, when the fourth field is set to a sixth value, the extension field comprises a plurality of extension payloads and padding.
 10. A receiving apparatus comprising: a receiver configured to receive a stream comprising a packet comprising a header and a payload; and at least one processor configured to implement an information extractor which extracts the header from the packet and extract information included in the header, and a signal processor which signal-processes a plurality of input packets included in the payload based on the extracted information, wherein a base field included in the header comprises a first field set to a first value representing that the base field is a first length or a second value representing that the base field is a second length, and wherein, when the first field is set to the second value, the base field comprises a second field representing least significant bits (LSB) of the pointer value indicating a first start point among respective start points of the input packets included in the payload and a third field representing most significant bits (MSB) of the pointer value.
 11. A controlling method of a transmitting apparatus using at least one processor, the method comprising: generating a packet comprising a header and a payload based on a plurality of input packets; signal-processing the generated packet; and transmitting the signal-processed packet, wherein a base field included in the header comprises a first field set to a first value representing that the base field is a first length or a second value representing that the base field is a second length, and wherein, when the first field is set to the second value, the base field comprises a second field representing least significant bits (LSB) of the pointer value indicating a first start point among respective start points of the input packets included in the payload and a third field representing most significant bits (MSB) of the pointer value.
 12. The controlling method of the transmitting apparatus of claim 11, wherein the base field comprises a fourth field representing an extension mode of the header, and the fourth field comprises at least one of information about whether an optional field is present, a length of the optional field, and a structure of an extension field.
 13. The controlling method of the transmitting apparatus of claim 12, wherein the fourth field is set to one of a third value representing that the optional field and the extension field are not present, a fourth value representing that the optional field is present and a length of the optional field is 1 byte, a fifth value representing that the optional field is present and the length of the optional field is 2 bytes, and a sixth value representing the optional field is present, the length of the optional field is 2 bytes, and the extension field has a structure comprising a plurality of extension payloads.
 14. The controlling method of the transmitting apparatus of claim 13, wherein when the fourth field is set to the fourth value or the fifth value, the optional field further comprises a fifth field representing a type of extension payload included in the extension field and a sixth field representing a length of the extension field, and when the fifth field is set to predetermined value, the extension field is completely filled by padding.
 15. The controlling method of the transmitting apparatus of claim 13, wherein when the fourth field is set to the fifth value, the optional field comprises a field representing a type of an extension payload included in the extension field, a field representing an LSB part of a length of the extension field, and a field representing an MSB part of the length of the extension field.
 16. The controlling method of the transmitting apparatus of claim 13, wherein when the fourth field is set to the sixth value, the optional field comprises a field representing a number of a plurality of extension payloads included in the extension field, a field representing an LSB part of a length of the extension field, and a field representing an MSB part of the length of the extension field.
 17. The controlling method of the transmitting apparatus of claim 16, wherein the extension field comprises a plurality of fields representing respective types of the plurality of extension payloads and a plurality of fields representing respective lengths of the plurality of extension payloads.
 18. The controlling method of the transmitting apparatus of claim 13, wherein, when the fourth field is set to one of a fourth value and a fifth value and a length of an extension payload included in the extension field is smaller than a length of the extension field, the extension field comprises the extension payload and padding.
 19. The controlling method of the transmitting apparatus of claim 13, wherein, when the fourth field is set to a sixth value, the extension field comprises a plurality of extension payloads and padding.
 20. A controlling method of a receiving apparatus using at least one processor, the method comprising: receiving a stream comprising a packet which comprises a header and a payload; extracting the header from the packet and extracting information included in the header; and signal-processing a plurality of input packets included in the payload based on the extracted information, wherein a base field included in the header comprises a first field set to a first value representing that the base field is a first length or a second value representing that the base field is a second length, and wherein, when the first field is set to the second value, the base field comprises a second field representing least significant bits (LSB) of the pointer value indicating a first start point among respective start points of the input packets included in the payload and a third field representing most significant bits (MSB) of the pointer value. 